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User Manual
Engineering Systems
COPYRIGHT NOTICE (C) Copyright Engineering Systems Pty Limited 1997-2010. All rights are reserved. The copyright applies to this manual and to the corresponding software (together referred to herein as the "licensed material"). DISCLAIMER Subject to limitations imposed by law, Engineering Systems Pty Limited makes no warranty of any kind in connection with the licensed material. Engineering Systems Pty Limited shall not be liable for any errors contained in the licensed material nor for any incidental or consequential damages resulting from the use of the licensed material. Engineering Systems Pty Limited is not engaging in the provision of consulting services in supplying the licensed material. Users of the licensed material are advised that output from computer software should be subjected to independent checks. Engineering Systems Pty Limited reserves the right to revise and otherwise change the licensed material from time to time without notification, or provision of revised material. SOFTWARE LICENCE The software is supplied to the user under licence. It may be installed on as many computers as required but the number of concurrent users must not exceed the number of licences held. For network licences, use is permitted only in the country for which the licence was supplied. The software may not be sub-licensed, rented, or leased to another party. The licence can only be transferred to another party at the discretion of Engineering Systems Pty Limited.
Engineering Systems Pty Limited 14 Eastern Road PO Box 85 Turramurra NSW 2074 Australia Tel: Fax: E-mail: Web: +612 9488 9622 +612 9488 7883 firstname.lastname@example.com www.microstran.com.au
July, 2010
Olympic Park Station The front cover features the multi-award winning railway station built for the Sydney 2000 Olympic Games. Architect: Hassell Engineer: Tierney & Partners Microstran model provided by courtesy of Tierney & Partners. Photography by Claire Morgan.
Microstran is a comprehensive software package for the analysis and design of all kinds of frame structures – beams, trusses, frames, towers, and bridges. The structures you can analyse with Microstran may be two-dimensional or three-dimensional, varying in size from a few members to many thousands of members. Chapter 1 – "Introduction" provides an overview of the capabilities of Microstran. Whether you are installing Microstran for the first time or updating an existing system, you will find all the necessary information in Chapter 2 – "Getting Started". Chapter 12 – "Input Tutorials" contains a number of exercises for guiding the new user through most of the basic operations required for doing a job. These tutorials emphasize the use of graphical input techniques that have become very important in modern structural software. Some of the tutorials are available on the Microstran website as "self-playing" demos. Chapter 3 – "Menus and Toolbars" provides a summary of the commands available and other chapters provide reference and technical information. This manual is available to the Microstran user on-line, together with comprehensive "pop-up" help for dialog boxes. The on-line help system provides a synchronized table of contents and powerful methods of searching for topics. If the file Readme.txt is present in the Microstran folder after installation, you should read it for information that became available after the manual was printed. The file is automatically displayed during installation but it may be displayed in Notepad at any time by double-clicking the file in Windows Explorer. The first version of Microstran fully compatible with this edition is V9.00.
1:Introduction 1
The Microstran Window........................................................................................................... 1 Toolbars...................................................................................................................... 2 Context Menus ........................................................................................................... 3 User-Friendly Features ............................................................................................................. 4 Input Methods........................................................................................................................... 9 Section Properties ................................................................................................................... 10 Modelling the Structure .......................................................................................................... 11 Loading................................................................................................................................... 11 Analysis .................................................................................................................................. 13 Display of Results................................................................................................................... 13 Reporting ................................................................................................................................ 14 Design and Detailing .............................................................................................................. 14 Program Capacity ................................................................................................................... 15 Computer Requirements ......................................................................................................... 15
2:Getting Started
Installing Microstran............................................................................................................... 17 Hardware Lock ....................................................................................................................... 18 Starting Microstran ................................................................................................................. 18 Font......................................................................................................................................... 19 How to Make a Shortcut on the Desktop ................................................................................ 19 Launch with Double-Click...................................................................................................... 19 Configuration.......................................................................................................................... 20 Microstran Commands............................................................................................................ 21 Shortcut Keys ......................................................................................................................... 22 Using the Mouse ..................................................................................................................... 23 Selecting Nodes and Members ............................................................................................... 24 Cursors.................................................................................................................................... 24 Right-Clicking on Nodes and Members ................................................................................. 26 The Node Properties Dialog Box............................................................................................ 27 The Member Properties Dialog Box ....................................................................................... 27 Properties Dialog Boxes with Multiple Selection................................................................... 28 Right-Clicking Away from Any Node or Member ................................................................. 28 Sets ......................................................................................................................................... 29 Printing in Microstran............................................................................................................. 30 Print and Print Preview Commands.......................................................................... 30 The Windows Print Dialog Box ............................................................................... 31
Microstran V9 Contents • i
The Page Setup Dialog Box ......................................................................................31 Configurable User Graphic .......................................................................................33 Steel Section Libraries ............................................................................................................34 Data from Earlier Versions .....................................................................................................36 Technical Support ...................................................................................................................36 Web Update.............................................................................................................................37 Tutorials & Examples..............................................................................................................37
3:Menus & Toolbars
Layout .....................................................................................................................................39 File Menu Commands .............................................................................................................40 View Menu Commands...........................................................................................................41 Structure Menu Commands.....................................................................................................42 Loads Menu Commands..........................................................................................................43 Analyse Menu Commands ......................................................................................................44 Results Menu Commands........................................................................................................45 Reports Menu Commands.......................................................................................................46 Show Menu Commands ..........................................................................................................46 Query Menu Commands .........................................................................................................47 Design Menu Commands ........................................................................................................49 Window Menu Commands......................................................................................................50 Help Menu Commands............................................................................................................50 Main Toolbar Commands........................................................................................................51 View Toolbar Commands .......................................................................................................51 Display Toolbar Commands....................................................................................................52 Help Toolbar Commands ........................................................................................................53 Draw Toolbar Commands .......................................................................................................54 Attributes Toolbar Commands ................................................................................................54 Load Input Toolbar Commands ..............................................................................................55 Results Toolbar Commands ....................................................................................................55 Steel Design Toolbar Commands............................................................................................56 OK/Cancel Toolbar Commands ..............................................................................................56 Extra Buttons Toolbar Commands ..........................................................................................57 Selecting Which Toolbars Are Displayed ...............................................................................58 Customizing Toolbars .............................................................................................................58 The Ouput Window.................................................................................................................59 Reset Control Bars ..................................................................................................................59
4:Structural Modelling
General ....................................................................................................................................61 Coordinate Systems.................................................................................................................63 Sign Conventions ....................................................................................................................64 Numbering Sequences.............................................................................................................66 Node Restraints & Member Releases......................................................................................67 Haunches.................................................................................................................................68 Coupled Shear Walls...............................................................................................................68 Concrete Slabs.........................................................................................................................69 Multi-storey Concrete Buildings .............................................................................................70
ii • Contents Microstran V9
Instability & Ill-Conditioning ................................................................................................. 72 Insufficient Support .................................................................................................. 72 Zero Stiffness at Node .............................................................................................. 72 Mechanism Instability .............................................................................................. 73 Ill-Conditioning ........................................................................................................ 74 Common Modelling Problems................................................................................................ 75 Unconnected Members............................................................................................. 75 Wrong Choice of Structure Type.............................................................................. 76 Angle Between AC and AB too Small ..................................................................... 76 Too Many Releases .................................................................................................. 76 Coplanar Nodes in Space Trusses ............................................................................ 77 Large Differences in Stiffness .................................................................................. 77 Columns Without Rotational Restraint..................................................................... 78
5:Structure & Load Data
Input Methods......................................................................................................................... 79 Numbering Sequences ............................................................................................................ 80 Job Title .................................................................................................................................. 80 Designer's Notes..................................................................................................................... 80 Units ....................................................................................................................................... 80 Structure Type ........................................................................................................................ 81 Node Coordinates ................................................................................................................... 82 Member Definition ................................................................................................................. 83 Fixed Supports (Node Restraints)........................................................................................... 87 Spring Supports ...................................................................................................................... 88 Section Properties ................................................................................................................... 88 Selection from Library ............................................................................................. 89 Shape Input............................................................................................................... 90 Property Value Input ................................................................................................ 91 Material Properties.................................................................................................................. 92 Selection from Library ............................................................................................. 92 Property Value Input ................................................................................................ 93 Node Mass .............................................................................................................................. 93 Rigid Member Offsets ............................................................................................................ 94 Semi-Rigid Connections ......................................................................................................... 95 Master-Slave Constraints........................................................................................................ 96 Tension-Only & Compression-Only Members....................................................................... 97 Cable Members....................................................................................................................... 98 Gap & Fuse Members ............................................................................................................. 99 Load Case Titles (CASE) ..................................................................................................... 101 Acceleration Loads (GRAV) ................................................................................................ 102 Node Loads (NDLD) ............................................................................................................ 102 Member Loads (MBLD)....................................................................................................... 103 Member Load Example .......................................................................................... 106 Member Distortions (DIST).................................................................................................. 107 Node Temperatures (TEMP) ................................................................................................ 109 Member Temperatures (MTMP)........................................................................................... 110 Prescribed Node Displacements (NDIS)............................................................................... 111 Area Loading ........................................................................................................................ 112
Microstran V9 Contents • iii
..................................................................................................................130 Load Input .....................................................128 Merging Two Models................................................................................................148 Trestle................................................................................................................................................................................................135 What SSI Does ..................................................118 Basic Drawing.........125 The Curve Command ...142 Trussed Rafter Portal Frame .................................................................................................125 Interrupting Commands...............................................................................................................................................................................................................................................................................................................................................133 7:Standard Structures Input 135 General ........................................................................................................139 Trusses .........................................131 Load Case Titles .................................................................140 Triangular Truss........................................................................................................................................148 Geodesic Dome ......................................................................................................................................122 The Drawing Plane...............138 Beam on Elastic Foundation ..........................................................132 Member Loads .......138 Continuous Beam....................................145 Grillage...........................................................................................................................................................................................Combination Load Cases (COMB) ...............142 Single Bay & Multi-bay Portal Frames...................................................................................................................................................................................................................................................137 Beams..................................................................................................................................................................................115 6:Graphics Input 117 General .....................................................................................................................................................131 Selecting the Input Load Case ........................................................................................124 Extrusion ..........................146 2-D Frame ..........114 Load Case Templates ................................................................140 Parallel Chord Trusses ........................................141 Portal Frames ...............................127 The Limit Command .....................................................................................................................................144 Sub-frame.....................................................................................149 8:Table Input iv • Contents 151 Microstran V9 .................................................................................................................................................118 The Drawing Snap Mode .........................................................................................................................................................................133 Combinations Load Cases...........136 Choosing the Structure Type.................................................................................................................................................................................................................................126 The Stretch Command.................................................................................................................147 3-D Frame ............................132 Area Loading ............................................................................117 Undo / Redo ..........................120 Shortcut Keys ...............................................................124 Automatic Removal of Duplicate Nodes and Members .................................................................................................................................................................................................................................................................131 Node Loads ......................................................................................................................................................................118 The Command Assistant ....................................................................................................................................................................................................................................................................................................................................................................................
............................................................................................. 174 Member Loads Group.......................................................................................... 176 Reinforced Concrete Design Group ........................ 174 Node Temperatures Group ..................... 168 Units Statement .................................................................................................................. 175 Design Block ......................... 179 Archive File Example ........................................................................... 151 How To Use Tables ............................. 173 Acceleration Group ................................... 155 Fixed Supports........................................................................................... 179 END Statement............. 169 Master-Slave Constraints Group ......................................................................................................................................................................................................................................................................................................... 177 END Statement............................................................ 157 Members................................... 173 Case Statement ............................ 163 Node Loads............................................. 168 Title Statements ................................................................ 169 Member Group ......................................................................................... 173 Node Mass Group.................................................................... 176 Design Data Statement ............................................................................................................................................................................................. 170 Member Type Group ............................................................................. 173 Load Block ......................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... 168 Designer's Notes Group ............... 178 Set Block.................................................................... 168 Vertical Axis Statement..................... 164 9:Archive File Input 167 Parameter Block....................................................................................................................... 152 Structure Entities .................................................................................................................................................................................................................................................................................................................................................................................. 170 Sections Properties Group .... 175 Combination Load Case Group .................................... 160 Section Properties...................... 162 Load Types .................................................................................................................................................................................................................................................................................................................................................................................... 171 Materials Group............................................. 175 END Statement........................................................................................................................... 160 Load Case Input................................................................................................. 170 Member Modification Group.................................... 176 Steel Design Group ......................................................................... 163 Member Loads........................................................................................................................................................................................... 157 Member Types............................. 180 Microstran V9 Contents • v ............................................................................................................................................................................................................................................................................................................................... 168 Structure Type Statement ....................................................... 155 Nodes........................................................ 169 Spring Supports Group .............................................................................................................. 174 Prescribed Displacements Group....................................... 169 Structure Block ............................................................ 173 Node Loads Group ..................................................................................... 169 Node Coordinates Group....................... 174 Member Temperatures Group ....................................................................General..........................................................................................
....215 Moving Loads Graphics ...........................................................................................................................................................................................................................194 Case Statement.........................................189 Member Types Group ..................209 Offset Load Cases – Grillages ...................193 Load Block ..............184 Units Statement..............................181 Parameter Block ............................................................................197 END Statement .........................................................................................................................................................................................................................................................................................191 Member Modification Group .....................................................................................................197 MLI Example .................201 Moving Loads – Beams..............................................................214 Distribution of Loads to Grillage ........................................188 Member Incidences Group..196 Prescribed Displacements Group .......195 Node Temperatures Group...............................184 Structure Type Statement.......................................................................................214 Example – HBL File .............................................................................................................10:Macro Language Input 181 General ......................192 Materials Group .............................................................................................................190 Reference Node/Axis Group..........................................199 Example ....................................................................................................................................185 Supports Group ............................................................................................................................188 Master-Slave Constraints Group.....................................................................................................................................194 Node Loads Group...195 Member Temperatures Group.........................................................................................184 Title Statements ....................................................................................................................184 Structure Block.......................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................191 Member Properties Group............206 Moving Loads – Grillages..............................194 Member Loads Group ................................................................................................................202 Load Types – Beams...........................205 Example – BBL File ..............................................................................................................................................................................................................216 12:Input Tutorials vi • Contents 225 Microstran V9 ..................................................................................................................................................................................202 Offset Load Cases – Beams .......................................185 Node Coordinates Group ..............................................................197 MLI Errors .......................................................................................208 Load Cases – Grillages .......................190 Member Releases Group....................................................................................................................................................................................................................................................................................................................................................198 11:Moving Load Generator 199 General ..................................................................................................................................................................................................................194 Acceleration Group.................................................................................................................................................................................................................207 Lane Definition .....................196 Combination Load Case Group............................................................208 Load Types – Grillages.................207 Area Definition ........................
......................................................................................... 273 Reactions Table ........................................................ 260 Response Spectrum Curves .......... 246 Accuracy........................... 253 Troubleshooting Non-Linear Analysis ................................................................................................................................................. 266 15:Reports 267 General................................................................ 248 Running a Non-Linear Analysis ................................................................................................................................................................................................................................................................................... 254 Elastic Critical Load Analysis ................................................................................... 246 Consistency Check ...... 272 Node Displacement Table ............................................................................................Tutorial 1 – Running an Existing Job .............................................................. 246 Residuals .................................................................... 260 Response Spectrum Analysis........................................................................................................................ 255 Selecting Load Cases for ECL Analysis.................................................. 243 14:Analysis 245 General................................ 245 Method .................................................................................................................................................................................................................................................................................................. 243 Windows Clipboard Operations...................................................................................... 256 Dynamic Analysis.................. 247 Non-Linear Analysis............................................................................................................................................................................................................................................................................................................................. 246 Linear Elastic Analysis ........................................ 251 Instability...... 271 Applied Loads ............................................................................................................. 270 Structure Data.................................................................................................................. 258 Analysis Control Parameters .............................................................................................................................................................................................................................................................................................. 274 Microstran V9 Contents • vii ....................... 267 Input/Analysis Report Options ................................................. 227 Tutorial 3 – A 3-D Example ................ 271 Condition Number ...................................................................................... 269 Report Contents ................................. 260 Running a Response Spectrum Analysis .......................................... 247 Second-Order Effects .............................................................. 267 Limiting the Scope of the Report............................................................................................................................................................................................................................. 258 Dynamic Modes ............................................................................................................................................................................................ 225 Tutorial 2 – Running a New Job ................................................... 265 Errors ........................................................................................................................................................ 242 Exporting a CAD DXF ................................................................................. 232 13:CAD Interface 241 General....................... 256 Analysis Control Parameters ..................... 270 Title Page....................................................................................................... 272 Member Force Tables........................... 241 Importing a CAD DXF ............................................................................................... 246 Condition Number .................................................................................... 259 Dynamic Analysis Example ...............................................................................................................................................................................................................................................................
......................................................................................298 Noding Eccentricity .............................................................................................................................................................................................................................................................................................277 16:Steel Member Design 279 General ................Residuals Table.............................................................................................................................................................................................................................280 Initializing Design Members ........................280 Design Data.....................................................292 17:Steel Connection Design 293 Overview.......274 Effective Lengths Table .........................................................................................................................................................................................................................................................294 Simple Shear Connections .......................................290 Updating Sections .........................................302 Interaction with Limcon ........................289 The Design Process ........................................................................................................................................................................................302 Report ............................301 Display Steel Connections ...........................276 Member Forces File .......................................................................300 Check Steel Connections ...........295 Splices ...............................................................................................................300 Steel Member Design..........302 18:Section & Material Libraries 309 General ......................298 Limitations of the K/N Connection Model ............................................................................280 Analysis ..............................................................................................................................................................................................................275 Exporting Results .......................................................................................................................................309 Section Library.....................................................................282 Graphical Display of Restraint Data ..............................................................................................................................................291 Computations ....................................................................................................................................................................................................................................................................................................................................................................................292 Steel Detailing.................................................................................................................................................................................................................299 Using Steel Connection Design..................309 viii • Contents Microstran V9 .......................................................................................................................276 Reactions File ....................................................................................300 Input Connection Data .......................................................................................................................................................................................................................................................296 Bracing Connections ............................................................................................................................................279 Section Library ..............................................................................................................................................................................298 Joint Bending Moments .............291 Obtaining Design Results.....................................................................................................................................................................................295 Moment Connections ..................296 Base Plates ............................................................................298 General.293 Virtual Reality Graphics in Microstran ..................................................................................................................................................................297 HSS Truss Connections.................................276 Node Displacements File ............................................................302 Connection Design Example ........................................................................274 Design Report Options .........................................................................................287 Selecting Design Load Cases ................................................................
................................................................................ 317 Limitations............................................................................ 318 Initializing Design Members ........................................................................................................................................... 342 Example 2 – Portal Frame ............................ 362 Index 369 Microstran V9 Contents • ix ............................................................................................................................................................................................................................................................ 313 The Material Library.......................................... 315 19:RC Design & Detailing 317 General.................................................................................... 324 Designing Columns ................. 358 Example 6 – Dynamic Analysis....................................... 336 The Header DXF ................................................................................................................................................ 321 Selecting Design Load Cases......................................................................... 312 Compiling a Library ....................................................................................................................................................................................... 327 Beam Design Computations .............................. 330 Reinforced Concrete Detailing Option .......................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... 338 Detailing Example ............................................... 337 Detailing Features.................................................................................................................. 326 Column Design Computations.......................................... 319 Default Values .............................................................. 328 RC Design Example ................................................................................................................................................ 323 The Design Process......................................................... 325 Designing Beams ................... 334 CAD Drawing Defaults ............................................................................................. 345 Example 3 – Space Truss................................... 325 Obtaining Design Results .............................................................................................................................................................. 354 Example 5 – Elastic Critical Load Analysis ........................................................................... 318 Section Axes .................. 339 20:Examples 341 Example 1 – Continuous Beam................................................................................................................................................................................................................................................. 349 Example 4 – Non-Linear Analysis.............................................Section Library Manager ........... 319 Design Data ..........................................
x • Contents Microstran V9 .
This gives rapid access to all the information about the current job. and output window are all dockable. and an output window at the bottom. toolbars on both sides. and Output from ancillary programs. Legends. This chapter gives an overview of the principal features of the system while more details are provided in other chapters.1:Introduction Microstran is a comprehensive software package for the analysis and design of 2-D and 3-D frames and trusses. toolbars. The Microstran Window THE MICROSTRAN WINDOW Main and Output Windows Microstran has a main graphical view bordered by a menu and toolbars at the top. Each Microstran V9 1:Introduction • 1 . Status information. The output window contains tabs for display of Query results. The menu bar. Check output.
is the principal command interface. Each menu title gives access to a dropdown menu of commands. FLOATING TOOLBAR Microstran toolbars have a number of additional features: • • • Tooltips – a pop-up window shows help for each button when the cursor rests over the button. Results. Optional large buttons – these are useful at higher screen resolutions. deleted.may be dragged to another edge of the main window. All of these are "dockable". The accompanying diagram shows the Draw toolbar positioned conveniently for graphics input. and Help toolbars. Display. The Menu Bar The menu bar. or floated inside the main window. In general. normally at the top of the Microstran screen. The edges of floating toolbars can be dragged to change the shape of the toolbar. and Extra toolbars may be displayed with the View > Toolbars command. OK. Note: You can change the toolbars in Microstran by adding buttons you need and removing buttons that you don't need. Microstran has View. They are customizable – buttons may be added. Load Input. The Steel Design. or moved. but may be docked on any other edge or dragged to any convenient location on the primary or secondary display and "floated". See Chapter 3 – "Menus & Toolbars" for a description of each of the drop-down menus. The above screen shot also shows the Table Input tree view of the data structure. Toolbars In addition to the main toolbar in the top left corner. each toolbar button corresponds to a menu item. Draw. Microstran V9 2 • 1:Introduction . Each one is initially docked on an edge of the main frame. Attributes.
This context menu provides a convenient shortcut to commonly used commands for viewing and manipulating the structure data. MAIN CONTEXT MENU Microstran V9 1:Introduction • 3 . CONTEXT MENU FOR DRAW COMMAND The diagram below shows the context menu that appears when you right-click in the main window with the cursor not close to a node or a member. This menu allows you to break the line (so you can start somewhere else). Context menus are fully implemented throughout Microstran. Context Menus A context (or pop-up) menu appears when you click the right mouse button.See Chapter 3 – "Menus & Toolbars" for more information. end the line (stop drawing). The diagram below shows the context menu that appears when you right-click during a Draw operation. or change the snap mode. giving rapid access to relevant menu commands without the need to search through the drop-down menus.
The Structure > Designer's Notes command allows you to store easily accessible descriptive information with the job. As well as being able to recover from mistakes. a typical example of which is shown below. 4 • 1:Introduction Microstran V9 . you can experiment with unfamiliar operations. TIP OF THE DAY Context-Sensitive (Pop-Up) Help Context-sensitive help offers the quickest and easiest access to information about what you see on the screen. Tip of the Day The Tip of the Day dialog box appears when you start Microstran. All dialog boxes in Microstran have context-sensitive help. You can find out what an item in a dialog box does just by clicking the question-mark button in the title bar and then clicking the item. knowing that it only takes one click to get back to where you were. CONTEXT-SENSITIVE (POP-UP) HELP Designer's Notes When you work on a Microstran model over a period of time it is helpful to have a few notes explaining any changes you make.User-Friendly Features Undo / Redo Undo makes your work so much easier.
section and material numbers. a pop-up window shows the node number. TOOLTIP IN A DIALOG BOX Data Tips When the cursor rests over a node. On-Line Help Microstran's on-line help allows you to browse help topics. The Microstran User's Manual is on-line through Help. ON-LINE HELP Microstran V9 1:Introduction • 5 . The tooltips in dialog boxes are similar to those that appear when the mouse cursor passes over a toolbar button. and releases. or do a full-text search for any word or phrase.Tooltips in Dialog Boxes In addition to the pop-up help available through the Help button. the node numbers. look through an index. For members. dialog boxes have tooltips. and support conditions (see screen shot on page 1). on-line help has the convenience of a synchronized table of contents. the data tip shows the member number. Employing HTML Help. the coordinates.
You can even print multi-column reports in landscape orientation. This aids recognition and provides a visual cue to help you relate the toolbar command and the menu command. The Page Setup dialog box below allows you to set print margins to the nearest millimeter. PAGE SETUP 6 • 1:Introduction Microstran V9 .Icons on Menus Microstran displays a small icon next to each menu item that has a toolbar button equivalent. There is an option to place your company logo at the top of all printed output. ICONS ON MENUS Page Setup Microstran takes advantage of built-in Windows facilities to produce professional printed reports and graphical output. The ability to control type size and select multiple columns provides flexibility and efficiency.
This allows you to make sure the output is what you want before printing it. The rows of each table may be sorted into ascending order by double-clicking on the header of the column by which the rows are to be sorted.Graphical Output As long as you have a printer installed Microstran will give you professional quality graphical output when you click the Print View button. Smart Help – The Command Assistant First-time users need intelligent help. for example. You can turn off this feature when you no longer require assistance. Note. Data may be transferred from or to the tables using Copy (Ctrl+C) and Paste (Ctrl+V). Double-clicking again reverses the sort order. The Command Assistant window appears automatically just when the first-time user is wondering what to do next. It disappears at the end of the command. Page orientation is chosen independently for graphics and reports. such as drawing or copying members. Undo (Ctrl+Z) may also be used. how section types and load types are clearly identified in the diagram below. Here is the Command Assistant window that appears during the Draw command. Microstran V9 1:Introduction • 7 . The Command Assistant is a popup help window that appears when you begin one of several common graphical tasks. The tree view provides a very convenient overview of all the data for the current job. Double-clicking any data item in the tree displays a table of all such items so you can easily edit them. The preview shows exactly what you will get on the printed page so you can check margins and page orientation without wasting paper. Print Preview Print previewing is available for graphics and reports. THE COMMAND ASSISTANT Table Input When you select Table Input all job data is displayed in a tree view similar to that in Windows Explorer. Specify the margins exactly as you want them and Microstran fills the available printing area with the graphical output. The icon next to each item in the tree view is a visual cue to its type. There is a data table for every type of data entity.
8 • 1:Introduction Microstran V9 .TREE VIEW AND DATA TABLE Shortcut Keys Shortcut keys. also known as accelerator keys give you the option of using a single keystroke for some commands. Both of these formats may be pasted into Microsoft Word documents. When you select the View > Copy command Microstran stores the screen image on the clipboard in EMF format. See "Shortcut Keys" on page 22. In programs such as AutoCAD. you can use the Paste command to directly insert this image. Enhanced Metafile Format (EMF) on Clipboard Microstran facilitates transfer of images to CAD and other programs by using the Enhanced Metafile Format (EMF) for the Windows clipboard. Pressing the Print Screen key on the keyboard writes a Windows bitmap to the clipboard.
tabular node and member data may be input using Table Input and then Graphics Input may be used to define section numbers. Grillages (including grillage on elastic foundation). multi-bay). Portal frames (single-bay.Input Methods Many different input methods are available to describe the structure and its loading. Trusses (triangular. The Standard Structure dialog box is shown below. erased. 2-D frames. Sub-frames. Standard Structures Input is often the easiest way to specify the input data for a range of common structure types. The structure type is selected and a small number of parameters that define the structure are then input. Graphics Input operates essentially as an intelligent CAD system specially designed for the task of structure and load definition. Graphics Input is often used in conjunction with other input methods because of the ease with which nodes and members can be selected visually. STANDARD STRUCTURES Structure types available include: • • • • • • • • • Microstran V9 Continuous beams. Powerful features are available for the generation of regular structures and loads are easily applied to groups of members or to a single member. 3-D frames. For example. 1:Introduction • 9 . or sub-divided. If your structure is similar to any of the standard types you may start with this method and then make any necessary changes with another input method. members may be drawn. copied. Using the mouse. moved. Trussed-rafter portal frames. Graphics Input for example. parallel-chord). The different methods may be used interchangeably so that it is possible to use the method that is most convenient for each particular input task. selecting members visually. Beam on elastic foundation. Graphics Input allows you to specify structure and load data graphically.
The automatic backup facility writes a file in this format. and tetrahedron). Macro Language Input operates from a data file called the MLI file that is prepared using a text editor. The archive file format is used to save input as a single file for storage but it also provides a convenient format for editing. SELECTION OF LIBRARY SECTION Microstran is supplied with a library of standard steel sections. Double-clicking an item in the tree presents data in a table for editing. CAD Input allows importing structure data directly from any 3-D CAD system that uses the standard format AutoCAD DXF (Release 12). With Table Input data may be exchanged between Microstran and other applications using the Windows clipboard. A tree control displays every item of job data in a convenient Explorerlike view. A number of libraries are available for sections originating in countries including Australia. Japan. for example) are quite similar to MLI files. Table Input allows you to enter structure and load data in tabular form. may be pasted directly into the node table. octahedron. and the US. For example. specified by section shape. Structure data may also be exported from Microstran to a CAD system. Geodesic domes (icosahedron. such as Microsoft Excel. Other programs may create archive files to be imported into Microstran. 10 • 1:Introduction Microstran V9 . The built-in capabilities of the macro language for data generation and repetition allow MLI files to be very compact. Section Properties Geometric section properties may be extracted from library files of standard steel sections. Archive File Input allows input to a text file called the archive file. X-bracing). For section shape input the required shape is selected from a range of common shapes and properties are computed automatically from the dimensions. Buttons are provided to insert and delete rows and to generate multiple rows. or entered explicitly. New Zealand. UK. node coordinates generated in a spreadsheet program.• • Trestles (K-bracing. Input files used by some other programs (STRESS and STRUDL.
The use of semi-rigid connections allows modelling of joints that are neither pinned nor fully rigid. facilitate the management of the data in the model for design and reporting. Modelling the Structure Gaps may be included in all numbering sequences – nodes. Note: In Microstran all entities have a number.You may change any library or create a new one using the Section Library Manager. Loading Microstran offers a full range of load types including area loads. Labels may be any integer value from 1 to 99000. referred to as a label. prescribed displacements. Members may be modified in a number of ways to model different types of structural element. and member distortions. sections and load cases – with no operational penalty. Master-slave constraints (kinematic constraints between nodes) facilitate the modelling of many kinds of structure such as "scissor" structures and floor slabs assumed to be rigid in-plane. Microstran V9 1:Introduction • 11 . Tension-only members and compression-only members may be used with non-linear analysis to model slender struts. members. Such gaps often simplify the data generation during input. and more readily accommodate changes during the design process. temperature effects. and situations where lift-off occurs. such as "X"-bracing. The catenary cable option allows the correct modelling of structures containing cable members. MEMBER LOAD TYPES Concentrated forces and moments may be applied at nodes and at intermediate positions in members. The option for gap and fuse elements permits the modelling of gaps and members that yield or fail at specified load levels. acceleration. Rigid member offsets permit the accurate modelling of stiff joint regions and stiff elements such as deep beams and shear walls. Uniform and trapezoidal distributed loads may be applied to members over all or part of their length.
Note: Only loads present on ALL members in a multiple selection are available for editing. one at a time. Temperature effects include node temperatures. Multiple Selection Load Editing You may select several members when using the Edit Member Loads command. Where a numerical value is shown for a node load component in the node load input dialog box. 12 • 1:Introduction Microstran V9 . Member distortions may be used to model "lack of fit" or prestress and also to generate influence lines. and axial member distortions. There is no limit either to the number of loads that may be applied to any member. EDITING A LOAD COMMON TO MORE THAN ONE MEMBER Multiple nodes may also be selected for the Edit Node Loads command.Acceleration may be applied in any direction to model gravity loads and inertial forces. The load components corresponding to any blank edit box will remain unchanged when you click OK. that load is present on all selected nodes. which includes acceleration loads. The Moving Load Generator option will create the multiple load cases necessary to model a series of loads moving along a continuous beam or an area modelled as a grillage (e. a bridge deck). uniformly distributed loads in global axis directions. Member loads that are common to all the selected members are displayed in the list box. These may then be selected.g. member temperatures. member centroidal temperatures. Combination load cases may be formed by factoring and combining primary load cases or other combination load cases. Changes to member loads in this dialog box are applied to all the selected members. for editing or deletion. and temperature gradients. or to the number of load cases. Entering a value in a blank box and clicking OK will set the corresponding node load component for all selected nodes. Cable members may be loaded with a restricted range of load types. A blank edit box indicates a node load component that is not the same on all selected nodes.
Analysis results may also be displayed numerically. Response spectrum analysis converts base shears to stress resultants throughout the structure and is most commonly used to model earthquake loadings. Display of Results Microstran displays applied loads and analysis results graphically. Dynamic analysis computes frequencies and the associated mode shapes for the natural vibration modes of the structure. non-linear elastic analysis. for any selected member. Bending moment and shear force diagrams may be shown for either or both principal axes. you may print it by clicking a toolbar button. elastic critical load analysis. Structure mass is computed automatically and additional mass may be specified as required. The Preview command shows exactly how the view will be printed. These are linear elastic analysis. Because the elastic critical load is dependent on the arrangement of load on the structure. with the option of annotating load and force diagrams with numerical values. Once the view shows the results required. The analysis may also be configured to use finite displacement theory instead of the conventional small displacement theory. A profile optimizer ensures the maximum efficiency in solution of large and complex structures. Microstran V9 1:Introduction • 13 . Elastic critical load analysis computes the elastic critical load for the structure and the true effective length for all members for selected load cases. in the output window. All analysis modules use a highly efficient equation solver giving unsurpassed speed and efficient use of disk space. these parameters will vary from load case to load case. Non-linear analysis may be configured to take into account the nonlinear effects of load displacement (P-∆ effect) and axial force in members (P-δ effect). and dynamic analysis with response spectrum analysis.EDITING A LOAD COMMON TO MORE THAN ONE NODE Analysis Microstran offers a number of types of analysis.
A summary (envelope) sorted by load case within section number. above. Design and Detailing Integrated design options use Microstran analysis results to check or design members of the structure. Results may be sorted by node and member or by load case. A summary (envelope) sorted by load case within member number. Full results for the members. 2. See "Input/Analysis Report Options" on page 267. Design modules are available for a range of national codes including: Steel • • • • • • • 14 • 1:Introduction AISC ASD – 9th Edition (1989) AS 1250 / AS 3990 AS 4100 – 1998 AS/NZS 4600:2005 BS 5950:2000 NZS 3404 – 1997 SSCJ/AIJ Microstran V9 . With this setting node results are sorted by load case within node number and member results are sorted by load case within section number.Reporting Microstran includes a flexible report generator. which allows you to restrict the contents of analysis reports to just the information required. You may independently include the member results in three different formats: 1. INPUT/ANALYSIS REPORT OPTIONS Summaries available when you select "Sort by node/section" in the report options dialog box. Envelopes of results for specified load cases may also be generated. and values may be reported at nodes or intermediate positions along members. 3.
Microstran V9 1:Introduction • 15 . with a suitable VRML "plug-in" installed. the number of load cases. you may need to set the OpenGL pixel format – see "Configuration" on page 20. To see the colour capability of your display. Colour printer. Virtual reality is only available on displays with 65535 or more colours. Note VRML graphics requires Internet Explorer. If your display has the necessary colour depth and virtual reality graphics is still not available. the capacity of the standard version is 35. Virtual Reality Graphics The Virtual Reality View button in Microstran displays a virtual reality representation of the structure. The number of load cases is essentially unlimited. 1024 x 768 resolution or higher. and the memory and disk capacity of the computer. which includes bar schedules. Display adapter memory and screen resolution are the main factors affecting the colour depth available. The reinforced concrete detailing option generates a CAD DXF for beams and columns.000 members. go to the Settings page of Display Properties in the Windows Control Panel. In appropriate circumstances. Program Capacity The capacity of Microstran depends on many factors including the type of structure.Reinforced Concrete • • AS 3600:1994 BS 8110 There are options for exporting information for steel detailing packages such as Xsteel and ProSteel. 32-bit colour. or an equivalent browser. Computer Requirements Recommended • • • • Windows XP or later. This may be imported into a CAD program to make a detail drawing. The necessary minimum colour depth is High Colour (16 bit).
16 • 1:Introduction Microstran V9 .
Some of the tutorial examples are available as self-playing demo files that can be viewed on your computer. Place the Microstran CD-ROM into your drive and the installation will start automatically. Setup will guide you through the installation process. Microstran V9 2:Getting Started • 17 . These files are on the Microstran CD-ROM and can also be downloaded from the Microstran website. You must have Administrator privileges to install Microstran. prompting you as required. A number of folders will be established under the specified Microstran folder.2:Getting Started Installing Microstran The Setup program will install Microstran on your computer. If you use the default name the folders as displayed in Windows Explorer will look like this: Several tutorial examples are included in Chapter 12 – "Input Tutorials" so that you can easily go through all the steps needed to do a typical job.
. Note the following help features. which make it easier for you to use Microstran: • There are tooltips on all toolbar buttons.. Created optionally during installation. this folder contains "self-playing demos". Programs to help convert data and section libraries from old versions of Microstran. .Utilities Hardware Lock Microstran is normally supplied with a hardware lock that must be attached to a USB port before you can start the program. Library files..Data ..Lib ... Folder for hardware lock drivers...... There is a prompt displayed on the left side of the status bar (at the bottom of the Microstran window) whenever the cursor is positioned over a toolbar button or a menu item. Select Start > All Programs > Microstran to start Microstran.. design parameter files... This folder is created optionally during installation..Folder Name Mswin . Additional set-up procedures are required for systems with a network lock.. Microstran User's Manual in PDF format..Drivers Comment Microstran folder – you can choose this name during installation. Mswin is the default.. Starting Microstran The Setup program creates a Microstran icon on the Windows All Programs menu.. Any drivers required for the hardware lock will be installed automatically when you install Microstran...PDF .Tutorials .. All Microstran program files and help files.. Microstran V9 • 18 • 2:Getting Started . Example and tutorial files – useful for testing and learning. and template files. Move the mouse cursor over the button for a moment and a little pop-up window displays the function of the button.. Default data folder – you can open Microstran files in other folders if you wish. These are described on data sheet supplied with the software.Examples ....Program .... Look here for prompts while you are performing input operations. and documentation files... network lock drivers.
Alternatively.exe file in the Microstran \Program folder. During installation this font is installed automatically using the file Linedraw. drag the Microstran icon from the Start menu to the desktop with the mouse while pressing the Ctrl key. It is convenient to be able to double-click on one of these files in Explorer to start Microstran with the job. Set the "Start in" folder to the data folder. and in the Create Shortcut dialog box browse to the Msw9. How to Make a Shortcut on the Desktop To make a shortcut to Microstran on your desktop (the background that is visible when no programs are running). look through an index. or search all help topic keywords. Enter Microstran for the name of the shortcut. the association may be re-established with the procedure set out below. Launch with Double-Click Microstran job files (Job. right-click on the desktop. Font Microstran requires the font MS LineDraw. and click the Finish button. When setting up Microstran on a workstation without installing from the CD you must ensure that MS LineDraw is installed. Use the Help > Microstran Help Topics command to display the Help Topics dialog box. you can browse the table of contents. If lost. The association between Microstran and the MSW file type may be established when Microstran is installed. where "Job" is the job name) should be identified in Explorer with the icon.ttf on the distribution CD. The Command Assistant. . Some items in dialog boxes also have tooltips. select New > Shortcut. available for most commands. the MSW file type must be associated with Microstran. Here are the steps necessary to make Microstran launch with a doubleclick: Microstran V9 2:Getting Started • 19 . displays a pop-up window listing the necessary steps.• • Context-sensitive (pop-up) help is available in most dialog boxes. With this. If unusual characters are seen in Print Preview it could mean that MS LineDraw is not properly installed or the system has not been rebooted after installation of the font.msw. To do this.
In the list box search for the Microstran job file type. Configuration settings are saved from run to run. which may be shown as either "Mswin Document" or "MSW File". Pop-up help is available for each item by clicking the button and then clicking the item. Select the File Types tab. Select the File Types tab. Configuration Microstran may be configured in many different ways according to your preferences. then select "Microstran Job File" in the list box and click the Edit button. you may delete all Microstran configuration data stored in the Windows registry by running the MsReset. Click the Change Icon button and then select the second icon. When you start a new job configuration settings are restored as they were at the last run. check that you have successfully set up your system by browsing to a Microstran job file and double-clicking. Some of the settings are also saved with the job data. and default library files and design codes. colours. so that when you open an existing job Microstran will be configured as it was when that job was saved. If found. Close the dialog box. The File > Configure command allows you to set items such as font size.exe program in the program folder. select this file type and click the Remove button. • • • • • • • • Now.• • • In Explorer select the View > Folder Options or View > Options command. Window location and size and toolbar locations are saved as they are when Microstran closes. If necessary. Microstran configuration settings are saved in the Windows registry under the HKEY_CURRENT_USER key. Click OK to close the Folder Options dialog box. In Explorer browse to the data folder and double-click on any Microstran job file (if the file name extension "msw" is not visible you may see it by right-clicking and checking the properties of the file). In the Description box type "Microstran Job File" and click OK. Click on the Other button and browse to Msw9. The dialog box shown below is for general configuration items.exe in the program folder. 20 • 2:Getting Started Microstran V9 . In Explorer select the View > Folder Options or View > Options command. The Open With dialog box appears. Click OK to close the Edit File Type dialog box. for each user.
you may need to set the pixel format. Microstran Commands Microstran commands may be performed by selecting an item on a dropdown menu. or right-clicking and then selecting an item on the context menu. Pick the nodes or members. as shown in the tooltip. Almost all the commands are available on the drop-down menus while some of them are also available on toolbar buttons or the context menu. only some of which are suitable for Microstran's virtual reality view. Contact Microstran support if you need help choosing an appropriate pixel format. Most commands operate on one or more nodes or members.FILE > CONFIGURE > GENERAL OpenGL pixel format On computers supporting OpenGL there are 24 or more pixel formats. You may use either of these command formats: Command-Then-Select • • Microstran V9 Select a command on a drop-down menu or click a toolbar button. WARNING: Use of an inappropriate value may crash your system. If your display has the necessary color depth OpenGL does not work. Commands selected from the drop-down menus are referred to in this manual as shown in this example: View > Zoom > Window Commands selected by clicking a toolbar button are referred to by the name of the button. clicking a toolbar button. 2:Getting Started • 21 . When the pixel format in the OpenGL Configuration dialog box is set to zero a suitable pixel format is chosen automatically.
Select a command on a drop-down menu. Select-Then-Command Shortcut Keys Microstran permits the use of shortcut keys to some commands. click a toolbar button. These standard Windows shortcuts may be used in dialog boxes. but in a dialog box it may delete text or do nothing. The shortcut keys used to control Microstran's main view are listed below: Shortcut Command Viewpoint left * Viewpoint right * Viewpoint up Viewpoint down Page Up Ctrl+Z Ctrl+Y F5 Ctrl+A Delete Home Esc Enter Space Zoom in Undo Redo Redraw Select all Erase members Zoom to extents/limits Cancel Confirm or OK Display next case/mode Page Down Zoom out * May be configured to rotate structure instead of viewpoint. pressing Delete usually deletes selected members. Shortcut Command Ctrl+C Ctrl+X Ctrl+V Ctrl+Z 22 • 2:Getting Started Copy Cut Paste Undo Microstran V9 . Pick the nodes or members. or right-click and choose a command on the context menu. For example. The effect of pressing a shortcut key depends on the context.• • • Right-click and choose OK on the context menu. Shortcut keys are also known as accelerator keys.
Using the Mouse Mouse functions are used in Microstran's main view to perform these operations: Function Click Right-click Double-click Click & drag left button Click & drag middle button Roll wheel Operation Select node or member Display pop-up menu Node or member properties Select nodes or members with "rubber band" box Pan Zoom view These mouse functions are used in the OpenGL view: Function Right-click Double-click Click & drag middle button Click & drag right button Roll wheel Operation Display pop-up menu Re-center on clicked point Pan Pan Zoom view Microstran V9 2:Getting Started • 23 .Ctrl+Y Ctrl+A Delete Home Esc Enter Redo Select all (in list box) Delete character Move caret to beginning of field Cancel OK See xxxx for shortcuts used in Graphics Input and yyyy for those used in the OpenGL virtual reality view.
when you have finished a command. • • Selected members are displayed with a dotted line while selected nodes are shown enclosed in a small square. which selects not only members enclosed by the box but also members cut by the sides of the box. below). For example. depending upon what is happening. then dragging the mouse until the selection box encloses the necessary nodes or members. releasing the left mouse button. All members may be selected by Ctrl+A (see "Shortcut Keys". Clicking again on a node or member deselects it. 24 • 2:Getting Started Microstran V9 . This is particularly useful with large or complex models. and finally. Selecting a predefined set.Selecting Nodes and Members Key concept. the cursor changes. Generally. Microstran allows you to repeat the command until you cancel the command by right-clicking. You may select nodes or members in several ways: • • Clicking each node or member in turn. Microstran lets you store a selection of nodes or members in a set (see "Sets". a "crossing window" appears. you then select members you want to erase and confirm the selection by right-clicking and choosing OK on the context menu. when you select the Structure > Erase Members command. right-click. and the standard arrow cursor will reappear. Microstran displays various cursors at different times. To terminate the command. The member selection cursor is still displayed. allowing you to choose more members to erase. "Dragging a selection box" means clicking (with the left mouse button) a point away from the nodes or members to be selected. Dragging a selection box that encloses the nodes or members to be selected. simplifying the task of reselecting a group of nodes or members every time you need to operate on them. These cursors are shown in the table below. above). Cursors Key concept. Note that when the selection box is dragged from right to left.
This cursor appears when you are selecting a zoom window or you are about to commence dynamic rotation. Microstran is waiting for you to click an end of a member. having clicked the "A" node of a member.Many commands are interruptible. When drawing members in a large model. Dynamic pan mode. If you drag a selection box from left to right. click a toolbar button. Right-click or press Esc to cancel from this mode. or select a node or member (the cursor changes as soon as you select a node or member). Microstran is waiting for you to select one or more nodes by clicking on them or enclosing them in a selection box. Microstran is waiting for you to select one or more members by clicking on them or enclosing them in a selection box. Dragging from right to left includes cut members. Microstran is waiting for you to click and drag the mouse to move the image. Right-click or press Esc to cancel from this mode. Node selection mode. It indicates that the viewpoint (or structure) is being rotated about a vertical axis. Member selection mode. cut members are excluded. drag from one corner to the diagonally opposite corner of the rectangle you want to zoom to. you may need to zoom in to another region of the structure before clicking the "B" node. Microstran V9 2:Getting Started • 25 . This cursor appears when you click and drag the mouse horizontally while you are using the Dynamic Rotate command. for example. click and drag to rotate the viewpoint (or structure). When zooming. You may use the Structure > Drawing Settings command or the context menu to change the snap mode without leaving the current drawing command. This cursor appears when you click and drag the mouse vertically while you are using the Dynamic Rotate command. Microstran is waiting for you to click and drag the mouse up (zoom in) or down (zoom out). When using the Dynamic Rotate command. This permits you to adjust the view during a command. Right-click or press Esc to cancel from this mode. Right-click or press Esc to cancel from this mode. Cursor Description Command mode. It indicates that the viewpoint (or structure) is being rotated about a horizontal axis. Look at the right of the status line to determine which snap mode is in effect. Dynamic zoom mode. Drawing mode. Microstran is waiting for you to select a command from the menu.
This is the context menu that appears when you right-click on a member: MEMBER CONTEXT MENU Double-clicking on a member is the same as selecting Properties on this menu. Microstran fully implements the Windows protocol for right-clicking on objects to obtain a menu of related commands – the context (or pop-up) menu. Right-clicking on a node displays this context menu: NODE CONTEXT MENU Double-clicking on a node is the same as selecting Properties on this pop-up menu.Right-Clicking on Nodes and Members Key concept. 26 • 2:Getting Started Microstran V9 .
MEMBER PROPERTIES DIALOG BOX Note: You may click on any other member and the contents of the dialog box will be updated for the new member. NODE PROPERTIES DIALOG BOX Note: You may click on any other node and the contents of the dialog box will be updated for the new node.The Node Properties Dialog Box The dialog box shown below appears when you double-click a node or select Properties after right-clicking a node. The Member Properties Dialog Box The dialog box shown below appears when you double-click a member or select Properties after right-clicking a member. This provides the simplest way to edit any of the member properties. Microstran V9 2:Getting Started • 27 . This provides the simplest way to edit any of the node properties.
28 • 2:Getting Started Microstran V9 .Properties Dialog Boxes with Multiple Selection Key concept. you can perform some operations in three different ways. you can display the section number on all members by clicking a button on the Display toolbar. Blank edit boxes indicate that the corresponding value is not the same for all of the multiple selection. The dialog box will display common properties of the selected group of nodes or members. Any changes you make will be applied to the whole group when you click Apply or OK. then right-click and choose Properties on the context menu. In effect. Right-Clicking Away from Any Node or Member When you right-click in the main window. away from any node or member. For example. You may select several nodes or members. by selecting the View > Display Options command. or by right-clicking and then selecting Section Numbers. the pop-up menu below appears. MAIN CONTEXT MENU This provides a very convenient alternative to the drop-down menus for many commands.
Sets are stored with the job so that once you have defined them they can be selected in subsequent runs. Renumbering the structure does not change the set. The Create Set command is also available on the node and member context menus. shown below. STRUCTURE > SETS SUB-MENU Create Set This command displays the dialog box below.Sets A set is a group of structure entities that may be referred to by name to facilitate selection. SET DATA DIALOG BOX Microstran V9 2:Getting Started • 29 . in which you may assign a set name and specify lists of entities in the set. Selecting the nodes or members in the set is then as simple as selecting the name of the set in the combo box drop-down list. The set name goes into the combo box on the View toolbar along with the names of any other defined sets. Sets are managed with the Structure > Sets sub-menu. After selecting nodes or members you may right-click and choose Create Set from the pop-up menu.
The File menu is shown in "File Menu Commands" on page 40 and the View menu is shown in "View Menu Commands" on page 41. These buttons are for Microstran graphics. 30 • 2:Getting Started Microstran V9 . Nodes are included in the set if they have all the selected node attributes and they lie within the coordinate ranges. The main toolbar is shown in "Main Toolbar Commands" on page 51. Microstran has a Print command on the File menu (File > Print File). You may now cancel the command with a right-click or proceed to select the members in another new set. usually located right under the menu. They correspond to the Print and Preview commands on the View menu. contains a Print button. File > Print Preview shows you how a report will be printed while View > Print Preview is for Microstran graphics. The print preview shows an exact image on the screen of the printed page. there is a Print command on the View menu (View > Print View) and this is used for printing pictures of the structure. Edit Set On selecting this command you may select a set from a list of all sets in the Select Set dialog box and then you may change any item for this set in the Set Data dialog box. The same command is initiated when you select a set from the combo box list on the View toolbar. The main toolbar. Create Member Set On selecting this command (also accessible from a button on the Extra toolbar) you may select members for inclusion in a new set. On confirming the selection on the context menu the Set Data dialog is displayed so you can enter the set name. This is for printing files and reports. and a Preview button. Select Set This command selects nodes and members in the selected set. . In addition to Print commands on the File and View menus. Also. Printing in Microstran Print and Print Preview Commands Microstran differs from many Windows application in that there is a requirement to print both files (reports) and pictures.Members are included in the set if they have all the selected member attributes and their centre lies within the coordinate ranges. As in a standard Windows application. Delete Set This command lets you select a set to be deleted. . not files or reports. Microstran has Print Preview commands on each of these menus.
close the preview window and then select the Print command on either the File or the View menu. The Page Setup Dialog Box The Page Setup dialog box allows you to change settings affecting the layout of printed output. Note: Clicking the Properties button displays the printer properties dialog box. View > Print Preview. The page orientation setting in the printer properties dialog box is ignored. When previewing a multi-page report file. Clicking this will initiate printing on the current printer. the Print button prints the whole file. or printer settings immediately before printing. either graphical or reports. When you click OK in this dialog box the selected printer becomes the current printer. Clicking the Print button on the main toolbar initiates a graphics print without the display of the Windows Print dialog box. When you see a print preview on the screen there is a Print button at the top left of the preview window. The preview is always for the current printer. Microstran maintains separate page orientation setting for graphics and reports. If you want to change the target printer after seeing a preview. all do not display the Windows Print dialog box. The view is printed immediately to the current printer – notice that the tooltip for the Print button shows the name of the current printer. File > Print Preview. If you want to print less than the full report use the File > Print File command and select the pages to be printed in the Windows Print dialog box. the number of copies. and the Preview button.The Windows Print Dialog Box The File > Print File and View > Print View commands display the Windows Print dialog box so you can change the target printer. WINDOWS PRINT DIALOG BOX Preview commands. Microstran V9 2:Getting Started • 31 .
You may also change the current printer in the Windows Print dialog box shown when you select either View > Print View or File > Print File. one for reports and one for graphics. shown in the Page Setup dialog box. as long as there is room on the page. is initially the Windows default printer and remains so until a different printer is selected. There are 72 points to the inch. Report Style When the number of columns is greater than 1 Microstran will print multi-column reports. These two settings. as required. for both reports and graphical output. See "Configurable User Graphic" on page 33. MICROSTRAN PAGE SETUP DIALOG BOX Text Size The text size. Orientation Microstran does not use the orientation setting stored with the printer properties. in points. A new current printer may be selected in the Windows Print Setup dialog box that is shown when you click the Change button. To increase the density of 32 • 2:Getting Started Microstran V9 . When there is insufficient room for the number of columns selected the number of columns is automatically reduced. are used instead. When the box is checked you may choose one of the available bitmap files from the adjacent combo box. The default value is 8. Margins Margins may be set independently for reports and graphics.The current printer. Logo Check this box if you want Microstran to print a logo at the top of each page of printed output.
DEFAULT GRAPHIC The specification of the bitmap is: • • • Width – 1200 pixels Height – 200 pixels Colours – 256 Bitmaps that do not match these requirements are not shown in the Page Setup dialog box. Microstran V9 2:Getting Started • 33 . Microstran prints the graphic in a space 50. Note: The Windows drivers for some printers do not support the printing of bitmaps. for example. When the scale is zero (default) the structure is plotted to fill the space available. On installation Microstran is configured to use the graphic shown below. With this option selected the graphic is printed on each page. The load case legend is only shown for the load cases for which loads are plotted. Microstran allows you to have a small graphic at the top of each page of printed output. which is always printed in its own colours. No colour Heavy lines Legends Scale Configurable User Graphic You may use this feature to place your company logo at the top of all printed output.printing in a report you may increase the number of columns and reduce the text size and margins. You can unselect the option in Page Setup if you do not want a graphic. even if using a colour printer.5 mm high. With a scale of 100. printing is in black only. 1 m on the structure is represented as 10 mm on the plot. The section legend is only shown when section numbers are included on the plot.8 mm wide by 8. This is more suitable for high-resolution printers. Graphics Style With the exception of the configurable user graphic. The scale at which structure geometry is shown. Any valid Windows bitmap file existing in the program folder may be selected in the Page Setup dialog box. Structure geometry is shown with heavy lines. which otherwise print a very fine line. If the option is not selected no graphic will be printed and no space will be allowed for it. Colour legends for sections and load cases may be shown.
Steel Section Libraries Microstran section libraries have a file name extension of "lib" and reside in the library folder.lib. Ukw. A source file is usually supplied with each steel section library. Any library. SECTION LIBRARY MANAGER Double-clicking a section in the right-hand tree displays a dialog box that lets you change any value stored in the library.lib. The source file is a text file with the file name extension "asc". for example) to an old standard library name (AS. or section may be sent from the left tree to the right tree by selecting it and then clicking the arrow button in the centre. section category. 34 • 2:Getting Started Microstran V9 .lib). which containing manufacturers' section data. Note: Any reference (in an old archive file. It is recommended that you do not modify the standard library supplied with Microstran – it is preferable to copy it to a file with a different name and then modify that. UK. The Configure > Section Library Manager command gives access to powerful facilities for editing an existing library or making a new library by merging sections and section categories from existing libraries – see Chapter 18 – "Section & Material Libraries". When a library is saved it may be compiled into a library file accessible to Microstran (see "Compiling a Library" on page 313). The Section Library Manager window shows a tree view of all available libraries on the left and a tree view of the destination library on the right. The Compute button displays derived section properties calculated by Microstran.lib) will be translated automatically to a reference to the equivalent new library (Asw.
SECTION PROPERTIES Compiling the saved library source file produces a report that shows any difference of 1% or more between original derived values and those computed by Microstran. COMPILING THE LIBRARY Microstran V9 2:Getting Started • 35 .
the version number.5. and licence details for your software. and V6. This information is required when you ask for technical support. submit a support request. Note: You may click the Check Version button in the Help About Microstran dialog box to determine whether your software needs updating. including V5. To import an archive file use the File > Import > Archive File command.5. or update your software – see "Web Update" on page 37.Data from Earlier Versions Microstran V9 reads MSW files from V8. HELP ABOUT MICROSTRAN 36 • 2:Getting Started Microstran V9 . where you may search FAQ topics for help. It can also import data in archive file format written by earlier versions of Microstran. Use the Help > About Microstran command to display the serial number. Note: Previous versions of Microstran cannot read files saved by Microstran V9 but may be able to import an archive file exported by Microstran V9. Technical Support Microstran technical support is available by telephone and e-mail. The Help About dialog box contains links to the Microstran website. V7. Editing the archive file may be necessary. If any error messages are displayed during the importing of the archive file it will be necessary to edit the file (File > List/Edit File command).
Each download is an executable file – run it to unpack the update files. which are referred to in Chapter 20 – "Examples". you may double-click on any one of them to see the tutorial. you will recognize the components you need to download.Web Update From time to time. clicking the Check Version button in the Help About dialog box displays the dialog box shown below. minor updates are provided on the Microstran website. Tutorials & Examples If you are new to Microstran it is recommended that you work through one or more of the tutorial examples in Chapter 12 – "Input Tutorials" to familiarize yourself with the operation of the principal menu and toolbar items. On installation you have the option of installing a number of "self-playing demos". If prompted for a password when this executable runs you must e-mail Microstran Support to obtain it. When new versions (or major upgrades) become available they are not available on the Microstran website – they may be purchased on a CD. This shows the dates of your Microstran software and dates of the current web downloads. Use the File > Open command to run one of these jobs. MICROSTRAN WEB UPDATE DIALOG BOX You can connect to the Microstran website by clicking the Downloads hot link in the Help About dialog box. Here. Microstran V9 2:Getting Started • 37 . You may use the web update facility to determine when an update is required. A new CD may be purchased as an alternative to using the internet download facility. In Windows Explorer. While your computer is connected to the internet. Each of these consists of an executable file in the tutorials folder. The Examples folder contains a number of example jobs. making it very easy to see whether an update is required.
any toolbar. This chapter lists all the commands available from the menu bar and all toolbars. Each toolbar button usually corresponds to a command on a drop-down menu. Note: See Chapter 2 – "Getting Started" for detailed information on the pop-up menus that appear when you right-click with the mouse. Some items on drop-down menus lead to sub-menus. or a context (pop-up) menu.3:Menus & Toolbars Layout The diagram below shows the layout of the Microstran window. LAYOUT OF MICROSTRAN WINDOW Microstran V9 3:Menus & Toolbars • 39 . All commands that appear on a toolbar have an associated icon. which is displayed when the same command appears on a menu. Each menu title gives access to a drop-down menu. Commands may be initiated from the menu bar.
Run another program. Reinstates the current job as it was at the time of the last automatic backup. Writes Microstran data to a file for input to another program. Configuration of program capacity. Microstran Archive file). intermediate file folder. colours. Change the printing options. Merge archive files for two models into a new archive file. Opens the selected file with the Microstran text editor for viewing or editing.g. Saves the current job using the same file name. Saves the current job to a specified file name and changes the name of the current job accordingly. Reads data into Microstran from a file (e. material library. Displays the selected file on the screen. and timed backup interval. Selects recently used job. Exits Microstran Run Recent Job Exit 40 • 3:Menus & Toolbars Microstran V9 . as it would appear printed. Also used for saving job in the form of a Microstran Archive file. section library. Prints the selected file. Closes the current job. Also used for editing of section and material libraries and dynamic response spectra. Opens an existing job.File Menu Commands FILE MENU Command New Open Close Save Save As Restore Backup List/Edit File Page Setup Print Preview Print File Import Export Merge Models Configure Action Creates a new job.
Change the orientation of the structure in the view. Copy view to Windows clipboard in EMF format. Displays the view as it would appear printed. Displace the view by the selected distance. Redraws the current view. Restrict input to a part of the structure by one of several available methods. Change the scale of the view or select a rectangular part of the view to fill the display window. Prints the view. Create a virtual reality view of the structure using OpenGL or VRML. Shows or hides the status bar. according to configuration. etc. member numbers. This reverses the effect of the Limit command.View Menu Commands VIEW MENU Command Toolbars Status Bar Redraw Viewpoint Zoom Pan Limit Action Shows or hides the toolbars. Select options for displaying node numbers. Full Copy Print Preview Print View Display Options Virtual Reality Microstran V9 3:Menus & Toolbars • 41 . Parts outside the limits are shown in light grey or hidden. Makes whole of structure available for input.
move members. including any that may not be visible. Selects all members. Move a node. Create. or delete a set. etc. grid spacing etc. Input notes relating to the job. rotate members. Erase selected members. edit. Specify structure type (plane frame. Insert a new node in a member. stretch nodes. Specify system of units. Snap modes for drawing members. polar copy. space frame. such as restraints.). etc. Reverse the A and B nodes of the selected members.Structure Menu Commands STRUCTURE MENU Command Title Designer's Notes Type Units Draw Members Erase Members Select All Sets Drawing Settings Attributes Move Copy Reverse Sub-divide Insert Node 42 • 3:Menus & Toolbars Action Input job description. Linear copy. reflect members. A set is a named group of entities forming any part of the structure. Microstran V9 . Draw members or input node coordinates. Input attributes of the structure. section numbers. select. Sub-divide selected members into a number of equal parts.
Delete load case. Create members with ends lying on arc or helix. Input prescribed displacement at specified nodes. Spreadsheet style of input. Loads Menu Commands LOADS MENU Command Add Case / Edit Title Import Load Case Template Select Input Case Exit Input Mode Delete Case GRAV Load Node Loads Node Displacements Microstran V9 Action Add new load case or edit title of existing load case. Select load case for input of loads. Input structure by selecting from common types. 3:Menus & Toolbars • 43 . Replace contiguous collinear members by a single member. Deselects input load case. Sub-divide a member into a number of segments whose ends lie on an arc. Renumber nodes and members (sort or compact). Add load cases specified in a load case template file. Input acceleration. Input loads at selected nodes.Intersect Join Curve Arc/Helix Renumber Standard Structures Table Input Insert new node(s) at intersection of selected members. preserving loads and design data.
Perform non-linear analysis (second-order). Analyse Menu Commands ANALYSE MENU Command Check Input Linear Non-Linear Elastic Critical Load Dynamic Response Spectrum Action Check structure and load data (normally automatic). Determine frame buckling load factors and buckling mode shapes. Copy member loads from source member to target members. Select cases for display of loads or results. 44 • 3:Menus & Toolbars Microstran V9 . Add response spectrum and static analysis results. Spreadsheet style of input. Perform linear analysis (first-order).Node Temperatures Member Loads Member Temperatures Area Loading Case Combinations Delete Load Edit Member Loads Copy Member Loads Table Input Moving Loads Select Display Cases Display Loads Input temperature at selected nodes. Input combination load case. Input loads on specified members. Input load per unit area on selected area. Display applied loads for selected cases. Determine natural frequencies and mode shapes. Change loads on selected members. Input temperature (gradients) in selected members. Generate load cases for moving loads. Delete selected type of load in selected load case.
shear force. Display structure in undisplaced position. Display results of member design check with colours representing range of design ratios. Esc to cancel. torque. or displaced shape. Select modes for display of buckling mode shapes. Display bending moment.Results Menu Commands RESULTS MENU Command Select Load Cases Select Natural Modes Select Buckling Modes Undisplaced Shape Member Actions Natural Modes Animate Modes Action Select load cases for display of loads or results. Show each currently displayed mode (natural or buckling) in alternate extreme positions. Buckling Modes Design Ratios Microstran V9 3:Menus & Toolbars • 45 . Select modes for display of vibration mode shapes. The legend in the output window shows the range of values represented by each colour. axial force. Press the space bar to show the next mode. Display vibration mode shapes. Display buckling mode shapes.
Create steel connection report. 46 • 3:Menus & Toolbars Microstran V9 . Create design report.). Highlight specified members. Not required – report is created automatically. Highlight members with specified section number.Reports Menu Commands REPORTS MENU Command Input/Analysis Steel Design Steel Connections RC Design Action Create report on structure and analyses performed. Highlight members connected to specified nodes. Highlight members of specified type (tension-only etc. Highlight members with specified material number. Show Menu Commands SHOW MENU Command Origin Section Material Member Type Nodes Members Action The origin of the global coordinate system is shown with a cross inside a circle.
List design results for design member containing 3:Menus & Toolbars • 47 Microstran V9 . Cancel current "Show" selection. Highlight specified set. List loads for selected node. List constraints for selected slave node. Highlight all nodes with non-zero added mass. List displacements for selected member.). List member data for selected member. List slave nodes for selected master node. List member forces for selected member. etc. Highlight initialized design members. List displacements for selected node. Highlight master nodes.Releases Rigid Offsets Semi-rigid Connections Master Nodes Slave Nodes Node Masses Design Members Sets Cancel Highlight members with specified type of release. Steel Connections Highlight steel connections. List reactions for selected (support) node. Highlight members with semi-rigid connections. Highlight members with rigid offsets. Query Menu Commands QUERY MENU Command Node Data Node Displacements Support Reactions Master Node Slave Node Member Data Member Displacements Member Forces Node Loads Member Loads Design Member Action List data for selected node (coordinates. Highlight slave nodes. restraint. List loads for selected member.
Display Structure Mass Show mass and CG location for structure. Note: Query data is displayed in the output window. 48 • 3:Menus & Toolbars Microstran V9 .selected member.
Design Data Design Load Cases Steel Members Update Sections Steel Connections RC Detailing Reinforced Concrete Design reinforced concrete members. Generates default design data for member. .Design Menu Commands DESIGN MENU Command Initialize Design Members Action . . For each design group. identifies member as beam or column. . Input or edit design data. Change sections to those selected in design. Microstran V9 3:Menus & Toolbars • 49 . Design or check steel connections. all designed sections are displayed and you may choose one of these for all members in the group. When design members are initialized they have no intermediate restraints. Design or check steel members. Sets design code for member. For RC design. Create CAD DXF of RC details for beams and columns. Select load cases for design of members. Permits linking of collinear members into a single design member. This data includes details of optional intermediate restraints.
Repositions output window at bottom of main view. Arranges windows side-by-side. Show or hide default attributes for new members. Contents. It may be turned off when no longer required. and Search. Show summary of keyboard shortcuts and mouse actions. Show Tip of the Day.Window Menu Commands WINDOW MENU Command Display Output Window Dock Output Window Cascade Tile Horizontally Tile Vertically Action Show or hide the output window. The Command Assistant offers pop-up instructions for most commands. Index. Help Menu Commands HELP MENU Command Microstran Help Topics Action Display Microstran HTML Help. Arranges windows above and below. Microstran V9 Command Help Tip of the Day Command Assistant Draw Member 50 • 3:Menus & Toolbars . so you can easily find help topics. There are three tabs. Arranges windows in an overlapped fashion.
Use the File > Preview command to preview a file.msw file. Save the job with its current name. Not available if button is greyed. Create a new job by choosing from one of several types and then inputting parameters. print a picture showing the current view of the structure. Dynamic rotate – drag to rotate. Not available if button is greyed. i. Standard Structures Input. Display oblique view. Display right view. The current job (if any) will be replaced by the new job. Redo.e. Print the view. Use the File > Print command to print a file. Open an existing job. The Help About dialog box includes links to the internet for support and checking the availability of updates. where "Job" is the name of the job as it was saved. display exactly how the graphics will be printed. Microstran displays the Open dialog box. Display top view.e. Undo the last action.Attributes About Microstran Display Microstran version and licence details. Table Input. This command is for opening an existing job – one for which there is already a Job. Main Toolbar Commands MAIN TOOLBAR • • Open a new job. in which you can locate and open the desired file. 3:Menus & Toolbars • 51 . • • • • • • • View Toolbar Commands VIEW TOOLBAR • • • • • Microstran V9 Display front view. Print preview. i.
Microstran V9 . Dynamic zoom – drag up or down to zoom. Increase scale for plotting loads. Display structure in virtual reality window. Display of node numbers. or displaced shape. right-click to stop. Display annotation of loads. Display section numbers. With Limit Set button not depressed. Pan – drag to pan. If the View > Limit command is in effect. With Limit Set button depressed. Display dialog box showing mass of structure. Display member numbers. With this button depressed view is limited to set selected in set combo box. right-click to stop. members in selected set are selected. Limit > Window.• Zoom to extents/limits of structure. Display symbols identifying steel connections. Display y axis for all members. clicking this button alternately displays the full structure and the limited part of the structure. Display node symbols. Limit > View Set command is invoked for selected set. Show/hide the output window. member forces. • • • • • • • • • Display Toolbar Commands DISPLAY TOOLBAR • • • • • • • • • • • • • • • 52 • 3:Menus & Toolbars Display symbol at origin of global axis system. Limit > Boundary. Display rendered view of structure. Zoom to window – drag window or click two points. otherwise. set is selected. Full View – this button reverses effect of Limit command. Display supports. Display pins. Display annotation of member force or displacement diagrams.
Microstran V9 3:Menus & Toolbars • 53 . member forces.• Decrease scale for plotting loads. or displaced shape. The Help Topics command starts Microstran HTML Help while Help About Microstran displays a dialog box showing version and licence details. The Help About dialog box includes links to the internet for support and checking the availability of Microstran updates. Help Toolbar Commands HELP TOOLBAR The Help toolbar contains buttons for the Help Topics and Help About Microstran commands.
Erase members. Rotate members. Set Middle/End snap mode. Set Intersection snap mode. Copy members (linear). Reflect members. Move members. Attributes Toolbar Commands ATTRIBUTES TOOLBAR • • • • • • • • Input fixed supports. Input material properties. Sub-divide members. Input master-slave constraints. Input section numbers. Copy attributes from one member to others. Intersect members. Input member orientation reference node/axis.Draw Toolbar Commands DRAW TOOLBAR • • • • • • • • • • • • Draw members. Input member releases. Copy members (polar). Display grid points and set Grid snap mode. 54 • 3:Menus & Toolbars Microstran V9 . Input section properties.
Input member loads – greyed if current input case is not a primary load case. Display bending moment. Display shear force. Display applied loads. You may input loads for the displayed load case. • • • • • Results Toolbar Commands RESULTS TOOLBAR • • • Display undisplaced structure. When no load case is displayed.Load Input Toolbar Commands LOAD INPUT TOOLBAR • • New load case. Display shear force. Current input load case – "P" indicates a primary load case and "C" indicates a combination load case. Input node loads – greyed if not inputting a primary load case. Select load cases for display. Input combination load case – greyed if current input case is not a combination load case. Fz. load input mode is in effect. Click the red "stop sign" button on the Load Input toolbar to exit load input mode. load input mode is not in effect. You must turn on this "switch" before you are able to select member forces for display. If you find that loads are still displayed when this button is not depressed. Exit load input mode. Mx. Display axial force. Fy. Input area load – greyed if current input case is not a primary load case. 3:Menus & Toolbars • 55 • • • • • • Microstran V9 . Click the arrow button to display a drop-down list box containing all existing load cases. Display member actions. Fx. My. Display torque.
Copy steel design data. Input steel design data. Query steel design member. Display member force envelope. Check all steel design members. Press the space bar to move to the next mode or Escape to exit mode animation. • • Steel Design Toolbar Commands STEEL DESIGN TOOLBAR • • • • • • Display steel design restraints. Display design ratios. Display reactions. Display or hide it with the View > Toolbars command. OK/Cancel Toolbar Commands OK/CANCEL TOOLBAR The OK/Cancel toolbar is an alternative to the context menu for confirming or cancelling selections. This toolbar is not displayed initially.• • • • • • Display bending moment. Display buckling modes. Design ratios are displayed graphically with different colours representing distinct ranges of values for the percentage of code capacity. Display natural vibration modes. 56 • 3:Menus & Toolbars Microstran V9 . Display displaced structure. Animate modes (natural or buckling). Mz. Each mode is displayed in turn. Check selected steel design members. For example. members shown bright red are loaded in excess of 110% of the design code capacity.
Zoom in. Node properties.Extra Buttons Toolbar Commands EXTRA BUTTONS TOOLBAR The Extra Buttons toolbar contains a number of buttons that may be added to other toolbars during customization. Microstran V9 3:Menus & Toolbars • 57 . Member properties. • • • • • • • • • • • • • Redraw (F5). Create member set. It is not displayed initially. Zoom out. Display or hide it with the View > Toolbars command. Rotate left*. Rotate up*. Display back view. Rotate down*. Display left view. Rotate right*. Insert node.
Any toolbar that has been customized may be reset to the original configuration by selecting it and then clicking the Reset button. All checked toolbars are displayed.Selecting Which Toolbars Are Displayed You may easily determine the toolbars that are displayed with the View > Toolbars command. This displays the dialog box shown below. On the Commands tab you may now select any existing toolbar and drag its buttons onto the new toolbar (or any other toolbar). it will disappear. 58 • 3:Menus & Toolbars Microstran V9 . This displays the Customize property sheet. Firstly. toolbars in Microstran are customizable in two ways. Secondly. Clicking the New button creates a new empty toolbar with any specified name. If you drag a button to a new position not on a toolbar. Customizing Toolbars As well as being dockable. while pressing the Alt key you may drag any button to any position on the same or another toolbar. you may click the Customize button in the Toolbars dialog box (View > Toolbars command). TOOLBARS DIALOG BOX You may also choose the flat style for toolbars or large buttons (these may be preferable at high screen resolutions).
is dockable. Reset Control Bars Control bars (i.e. If you have "lost" any toolbar or the output window you can easily restore program defaults by executing the MsReset. toolbars or the output window) may be inadvertently positioned off the visible screen. You may double-click on the title bar of the floating output window and it will return to its previous docked position.CUSTOMIZING TOOLBARS The Ouput Window While the output window is docked you may drag the inner edge to change its size. The output window. The position of the output window and each toolbar is persistent from run to run. You may click on any part of the edge of the output window and drag it so that it floats anywhere on the primary or secondary display or docks on any edge of the main window.exe program located in the Microstran program folder. normally at the bottom of the main window. Click the output window button to hide or display the output window. Microstran V9 3:Menus & Toolbars • 59 .
60 • 3:Menus & Toolbars Microstran V9 .
Each node is free to displace under load in the six global directions unless that node is restrained. space truss. or truss elements. See "Structure Type" on page 81. The resulting distortions of each member are obtained from the displacements of the nodes and then the corresponding member forces are calculated. Structure Type In Microstran. plane frame. and a set of members connecting the nodes together. grillage. a plane frame in the XY plane will have node restraints applied so that displacements out of the plane (Z translation) and rotations in the plane (X and Y rotations) are prevented. The structure is represented by a set of nodes. frame. each model has a structure type. restraints are automatically applied to all nodes to enforce the displacement pattern implicit in the structure type. space frame. as a mathematical model suitable for analysis by the computer. the stiffness properties of the structure are calculated and for each load case the elastic displacements of each node are determined.4:Structural Modelling General Structural modelling is the process of representing a structure. See "Node Coordinates" on page 82 and "Fixed Supports (Node Restraints)" on page 87. each node may have up to six degrees of freedom (DOF) – translation in the three global axis directions and rotation about these axes. or plane truss. For all structure types except the space frame. each of which usually corresponds to a joint. each part of the structure is idealized as a line element – line elements are also known as beam. In Microstran. Nodes In a space frame. Microstran V9 4:Structural Modelling • 61 . During the structural analysis process. The analysis process will compute the displacement component in each of the six global directions where node restraints have not been applied. For example. and any loads applied to it.
if you wish to determine secondary moments in a roof truss the structure type should be plane frame. When the structure type is either space truss or plane truss member releases are automatically introduced at each end of all members. Load Cases There are usually a series of primary load cases each representing separate conditions such as dead load. Axes are associated with each member and these are used as a frame of reference for member loads and member forces. concentrated node loads. Trusses In practice. For example. Many types of load are available. Member releases or semi-rigid connections may be introduced at the ends of the members. each member in a framed structure is rigidly connected to the nodes at the ends of the member. with load combinations assembled from the primary load cases to represent design conditions for strength and serviceability. 62 • 4:Structural Modelling Microstran V9 . gravity loads. concentrated and distributed member loads. live load.. a "truss" is usually modelled as a frame. Each load case comprises any number of these loads in any combination. See "Member Definition" on page 83. while the frame structure type must be used if you wish to determine bending moments in any member of the structure. wind load etc. axial and transverse temperature gradients. The truss structure type is used for pin-jointed models. and member distortions. not as a truss.Members By default.
Microstran V9 4:Structural Modelling • 63 . except in the case of angle sections where you have elected to use principal axis properties. Member forces and displacements are reported with respect to the member axes. The first node is the "A" node and the second is the "B" node. The global axes may be oriented in any direction but usually. the "C" node. Node loads and displacements are defined with respect to the global axes. GLOBAL AND MEMBER AXES Global Axes XYZ The global axes are a right-handed set of orthogonal axes used to define the geometry of the structure. Member Axes xyz The section axis YY is usually aligned with the y member axis but you may align the XX section axis with y instead. The positive direction of the x axis is determined by the order in which the end nodes of the member are specified. A third node. either the Y or Z axis is directed upwards. Member axes (also referred to as local axes) are sets of right-handed orthogonal axes attached to each member in the structure. A global axis may be used instead of the "C" node.Coordinate Systems Two types of coordinate system are used to describe the structure – the global axes and a set of member axes for each member. Member loads may also be defined with respect to the global axes. The x axis runs along the length of the member coincident with the member centroidal axis while the y and z axes are usually coincident with the principal axes of the cross-section. See "Section Properties" on page 88. Member loads may be specified with respect to member axes. These are shown in the diagram below. is used to define a plane containing the y axis.
This choice is appropriate when bending is not significant or the section is assumed to be constrained to bend about a rectangular axis. actions are positive if they act in a clockwise sense when viewed along the positive direction of the axis about which they act. items are positive in the positive direction of the axes to which they refer. Transverse member loads are always referred to the member y and z axes (rectangular). Node loads.Angle Sections With angle sections the rectangular axes and member axes are always located by the reference node/axis but you have the choice of using either rectangular axis properties or principal axis properties. An "engineering" sign convention is used so that positive bending moments cause sagging and negative bending moments cause 64 • 4:Structural Modelling Microstran V9 . that is. Sign Conventions In general. the "righthand" rule applies. For angular displacements and moments. When you choose rectangular axis properties they are used as if they were principal axis properties and results are referred to the member y and z axes (rectangular). When principal axis properties are used the member principal axes are rotated from the member y and z axes and results are referred to these (rotated) axes. displacements and reactions are specified with respect to the global axes. This choice is made when you select the section from the steel section library. The diagram below shows positive node load components. Loads applied to members may be specified with respect to either the global axes or the member axes. Choose principal axis properties for angles that are free to bend about the principal axes. POSITIVE NODE LOAD COMPONENTS Member end forces and moments are computed with respect to the member axes.
are plotted in the display plane at right angles to the member. POSITIVE MEMBER FORCES Microstran V9 4:Structural Modelling • 65 . If the gradient of the x axis is positive. The sign convention for plotting axial force and torque depends on the projection of the member on the display plane. Positive member end actions and the corresponding distortions are shown in the diagram below. To assist in interpretation. positive values are plotted on the upper side of the member. compression is shown in a broken line. not being associated with either principal plane of the member. Unless a negative scale factor is set.hogging. bending moment diagrams are displayed on the tension side of the member. Axial force and torque diagrams. Shear force and bending moment diagrams are plotted in the corresponding principal plane of the member.
The profile optimizer performs internal renumbering of the nodes to minimize the profile of the structure stiffness matrix (see Chapter 14 – "Analysis"). If parts of the structure are added or deleted. chord etc. column. 66 • 4:Structural Modelling Microstran V9 . Numbering Section Properties Microstran steel member design programs use the concept of a "design group".g. Numbering Nodes The automatic use of the profile optimizer means that you are not constrained in the way you number nodes. If a design program is being used it is advisable to consider the sequence in which section properties are numbered. Numbering Members Solution time and storage requirements are quite independent of the sequence in which member numbers are assigned. During the design process. allowing the design to automatically take into account the forces and moments in every member in the group. Use the Structure > Renumber commands to rearrange node numbering at any stage. There is no penalty either in solution time or in storage requirements when gaps occur in any numbering sequence. You may leave gaps in numbering sequences for maximum convenience in entering or generating data and in interpreting the results. the section used for any design group may be changed. there is no need to renumber nodes and members. and section properties) and load cases.Numbering Sequences Numbers are used throughout Microstran to identify structure elements (such as nodes.). beam. members. Use the Structure > Renumber commands to rearrange member numbering at any stage. Each group of members that must be of the same section should have a unique section number. All members which have the same section number may be treated as a single design group. It is often convenient to allocate member numbers in blocks for each type of member (e.
Case 1 shows the usual situation with a pinned support and no member release. Case 3 shows a pinned support AND a moment release in the column. all DOF restrained except Z rotation) and the member release code is 000000 (i. Microstran V9 4:Structural Modelling • 67 . The node restraint code is 111110 (i. This structure is unstable and analysis would stop with a "zero stiffness" or "structure unstable" error message for the support node. NO releases). Case 2 shows an alternative arrangement with a fixed support and a member release. release about member z axis only). The diagram below illustrates the modelling of a pinned support at the base of a column in a plane frame.e. restraint at all DOF) and the member release code is 000001 (i. The node restraint code is 111111 (i. The node is shown as a solid block to highlight the difference between a "pin" resulting from the absence of a node restraint and that resulting from the inclusion of a member release.e. The analysis would give identical results but the rotation at the base of the column would be unknown because it is not fixed to the node (whose rotation is known).e.Node Restraints & Member Releases Member releases are used to create internal hinges in a framed structure and they should not be confused with node restraints. see "Fixed Supports (Node Restraints)" on page 87 and "Member Definition" on page 83. which define the supports of the structure.e. MODELLING A PINNED SUPPORT For further examples of the use of node restraints and member releases.
so that a tapered member must be modelled as a number of segments. As a result. Standard Structures Input automatically computes the section properties of haunches fabricated with specified steel sections. Each haunch may be modelled with as many as 6 segments. As a result. between the node and the adjacent end of the member. Coupled Shear Walls Rigid member offsets prevent all deformation. where shear walls or large columns are coupled by beams. Haunches in portal frames can usually be modelled satisfactorily with two such segments. the axial stiffness of the columns would be overestimated. The recommended method of modelling coupled shear walls is illustrated below. See "Single Bay & Multi-bay Portal Frames" on page 142. For example. The section properties at the mid-point of the tapered segment may be used for the corresponding prismatic member. COUPLED SHEAR WALLS 68 • 4:Structural Modelling Microstran V9 . if rigid links are used in the column members throughout the depth of the beams. sidesway of the structure under lateral load would be underestimated. including axial deformation. rigid offsets should be used with caution in structures where the behaviour depends significantly on the axial deformation of some members.Haunches All members in a Microstran structural model are prismatic line elements. each of a different cross-section.
to fit around an opening. Microstran V9 4:Structural Modelling • 69 . GRILLAGE SLAB MODEL Here are a few recommendations for using this technique: • • A sub-division of each span into about 8 beam strips in each direction would usually provide very accurate results. The arrangement of the beam strips may be varied to conform to the shape of the slab. EQUIVALENT FRAME METHOD A refinement of this method involves the use of a grillage to model the slab.Concrete Slabs Two-way slab systems are often designed using the "idealized frame" method in which a fairly regular building is assumed to behave as two series of equivalent frames at right angles. The nearest beam strip should be as close as possible to the centroid of an edge beam. for example. For each column grid line there is an equivalent frame in which the properties of each horizontal member are usually assumed to be those of the full width of the slab between the centres of the adjacent spans at right angles. A large model may result for structures with more than a few spans. It is convenient because it leads to a rational distribution of reinforcement when each beam element is uniformly reinforced for the design actions in it.
If you are uncertain about how a service core behaves. so if using a GRAV load for calculating self-weight use half the actual density for the slab material. it is usually necessary to take into account the contribution of the floor slabs in the resistance of horizontal loads. Reinforced Concrete Service Cores Generally. However. it may be advisable to consider two or more alternative models in which different assumptions may be tested. The total volume of beam strips will be twice the volume of the slab. For each horizontal member framing into the equivalent column. Care should be taken in considering what values to use for the effective width 70 • 4:Structural Modelling Microstran V9 . The torsion constant is a measure of the stiffness of a member in uniform torsion so it underestimates the torsional stiffness of a building core whose crosssection can warp. In effect. a service core may be modelled as an equivalent column located at the centroid or the shear centre of the cross-section. • Multi-storey Concrete Buildings It is not uncommon to analyse a reinforced or prestressed concrete building as a frame even though it may contain planar elements such as walls and floor slabs. Calculation of the torsion constant of the equivalent column presents difficulties if the service core cross-section is capable of warping. the slab is replaced by a network of equivalent beams connecting each vertical element to adjacent vertical elements. if the service core has an open cross-section or if lintels provide insufficient coupling between adjacent walls for it to be regarded as a closed crosssection. For a closed cross-section warping is small and the torsion constant gives a reasonable measure of the torsional stiffness of the core. warping will occur in torsion. A possible approach to this problem is to compute the torsion constant as if for a closed section and to reduce it by an empirical factor that takes into account the reduced torsional stiffness of a core that warps. Such cross-sections are torsionally flexible for uniform torsion (St. a rigid offset is used for the region between the face of the service core and the node of the equivalent column.• The properties of each member should be those of the rectangular section of the beam strip with the exception that the following reduced value should be used for the section torsion constant. There must be equivalent members in both directions. Concrete Slabs In analysing the building frame. Venant torsion) but stiff for non-uniform torsion (which occurs because of the vertical distribution of any torsional load and also because the base of the core is fixed). J = 1/6 × B × T3 where B is the width of the beam strip and T is the slab thickness.
for instance. It may be reasonable. Note that member incidence (the "direction" of the member) is not changed by the sorting operation. The accuracy of the solution may also be improved by the inclusion of master-slave constraints. This creates a column at each node – erase any that are not required. is not used (see "Concrete Slabs" on page 69). use the Structure > Copy > Linear command without extrusion to produce as many copies of the typical floor module as required. a. a concrete floor slab can be regarded as being rigid in its own plane (i. the full width of the slab. Generally. to use code rules regarding the effective width of a tee beam. Inputting a Multi-storey Model A systematic procedure should be adopted for inputting a large structural model. c.of these beams.e. using arbitrary values at this stage if necessary. the floor undergoes rigid-body motion only). Copy the typical floor module to a new job and in the new job. d. this fact can be used to permit the saving of three DOF at each node in the floor except for one arbitrarily selected as the "master" node (see "Master-Slave Constraints" on page 96). Usually. b. The network of equivalent beams should be arranged so that "racking" of the floor is inhibited if master-slave constraints are not used. has been used successfully for multi-storey models. Microstran V9 4:Structural Modelling • 71 . Create typical floor module Start by drawing equivalent beams in the XY plane. The "Connect collinear members" option may be selected if desired. Propagate typical floor module Change the vertical axis from Y to Z using the Structure > Type command. When the floor is finished. The procedure set out below. It is a good idea to use the File > Save As command to save the job with a new name at critical stages. Input all sections and materials. used in the design of the slab itself. Graphics Input is very convenient because the model can be input directly from the typical floor plan. which uses Graphics Input. Sort nodes and members Use the Structure > Renumber command to sort node and member numbers. It does not matter how the software allocates node and member numbers because these can easily be rearranged in order. The primary and secondary sort directions should be Z and Y respectively. Erase all beams at the lower level. Draw beams from left to right and from bottom to top on the screen. copy all members to the level above with node extrusion. If the Microstran Master-Slave Constraints feature is available. in plan. Input rigid offsets and master-slave constraints Rigid offsets and master-slave constraints are most conveniently input using Graphics Input.
The model representing the typical floor module should be maintained as a separate job because the procedure of building up the model will have to be repeated if changes are required. Ill-conditioning may also occur if there is an excessive difference in stiffness from one part of the structural model to another. Instability and ill-conditioning are properties of the structure. An ill-conditioned structure is usually one that is almost unstable. too many member releases. Input restraints. The most common error conditions are described in this section. not of the loading condition. INSUFFICIENT SUPPORT Zero Stiffness at Node If there is zero stiffness for any DOF at any node a force or moment could be applied at that DOF without any resistance and so it would be 72 • 4:Structural Modelling Microstran V9 . Insufficient Support If insufficient supports have been specified for overall stability of the structure. They are usually caused by insufficient node restraints. or inappropriate values for some section properties. See also "Common Modelling Problems" on page 75. loads etc. Ill-conditioning occurs if a solution is obtained but with severe loss of numerical precision. Any convenient method may be used to complete the model. This condition will be detected before analysis is started and an error of the following form will be reported: STRUCTURE HAS INSUFFICIENT SUPPORT Case 1 in the diagram below shows a simply supported beam with insufficient support. f.e. Instability & Ill-Conditioning Instability occurs if a structure or a part of it can move without any resistance. producing gross displacements during analysis. In this case no solution can be obtained. Add non-typical parts Any parts of the structure that were not generated by the propagation of the typical floor should now be added. analysis is not possible.
Unstable nodes can be eliminated by applying a restraint to the zero stiffness DOF at the node. An unstable node is shown in Case 1 in the diagram below. Mechanisms may be eliminated by applying a restraint to the DOF reported in the error message but you should consider whether the error is a symptom of a more fundamental problem with the structural model such as a missing support. an inappropriate section property value. Microstran V9 4:Structural Modelling • 73 .impossible to calculate a displacement in that direction. in which there was found to be no resistance to displacement. Nodes are represented as solid blocks. DOF 1 2 3 Direction X Y Z DOF 4 5 6 About Axis X Y Z A node where a zero stiffness error occurs may be referred to as an unstable node. The DOF number. A mechanism will be detected during analysis as an attempt to perform impossible numerical operations at a particular DOF and one of the following errors will be reported: STRUCTURE UNSTABLE AT NODE nnnnn DOF f or ZERO PIVOT AT NODE nnnnn DOF f where "nnnnn" and "f" are as defined above. or an incorrect member release. These errors are detected at an early stage of analysis and reported with an error of the form: ZERO STIFFNESS AT NODE nnnnn DOF f where: nnnnn f = = The node number at which instability was detected. ZERO STIFFNESS AT NODE Mechanism Instability If a structure has any part that can move freely. it is actually a mechanism and cannot be analysed. as shown in the table below.
MECHANISM INSTABILITY Zero stiffness at a node in a direction that is not parallel to a global axis is also detected as a mechanism during analysis. is a measure of how much precision was lost. the results may be meaningless and the structure may well be unstable. where the frame has pinned supports and also has pins at the top of each column. Ill-Conditioning If severe loss of numerical precision occurs during analysis the structure is ill-conditioned. This type of instability cannot be eliminated by specifying a restraint (in a global axis direction) but by adding a link member or a spring in a non-global axis direction. A displaced shape plot of an ill-conditioned structure would usually show gross displacements.A mechanism is shown in Case 1. A warning is generated if the condition number exceeds 10E4. The condition number. in the diagram below. Important Note: It is possible for ill-conditioning to occur without a discrepancy in the equilibrium check – a satisfactory equilibrium check is not a guarantee that the analysis was successful. 74 • 4:Structural Modelling Microstran V9 .POSSIBLE MODELLING ERROR In this case. a large condition number will also be reported and the results should be regarded as being meaningless. the structure would be stable. After analysis Microstran performs an equilibrium check in which the external forces are compared to the sum of the member forces at each node. If any one of the four pins were removed. reported on the screen after analysis. If this check shows a discrepancy the following error message will be reported: LARGE RESIDUAL . When an analysis has been completed with a large condition number being reported. Microstran cannot determine at what point the illconditioning becomes unacceptable so that you should always check the condition number (see "Report Contents").
In the diagram below.Common Modelling Problems Unconnected Members Sometimes. for example. so that the central column (6-3) is connected to it. 2-3 and 3-4. above. if the rafter is input as a single member (2-4) from node 2 to node 4. member 2 Microstran V9 4:Structural Modelling • 75 . it may not be evident that a single member has been input instead of two or more connected end-to-end. The rafter must be input as two members. If this occurs. it can give rise to unconnected members at the interior nodes. The warning message displayed in the output window for the structure in Case 1. UNCONNECTED MEMBER Unconnected members are detected in the checking phase that precedes analysis. would be similar to: Nodes adjacent but not connected to members: Warning: node 3. You may use the Analyse > Check Input command to see warnings about unconnected members. the central column will not be connected to the rafter and it will be unstable.
In many cases. Stability of the structure depends on bending moment at any point. illustrated in Case 1 in the diagram below. a "zero pivot" error will result – see "Mechanism Instability" on page 73. When the angle between AB and AC is zero the computation is impossible.Wrong Choice of Structure Type Plane truss and space truss structure types are rarely used nowadays. • 76 • 4:Structural Modelling Microstran V9 . It occurs if the specified reference axis for a column is the vertical axis and in any other situation where the vector to the reference node is almost parallel to the longitudinal member axis (x). Fix the problem by double-clicking on the affected member and changing the reference node/axis. Angle Between AC and AB too Small Member nn ref. The structure type must not be "plane truss" or "space truss" if any of the following conditions exists: • • • You want to determine bending moment at any point in the structure. may be avoided by any of the following procedures: • Set the structure type to plane truss or space truss (as appropriate). Too Many Releases If a zero stiffness error is reported at a node in a plane frame or space frame it is usually because all members connected to the node are pinended. If you attempt to analyse a structure that is incorrectly classified in Microstran as a truss. the default reference axis is suitable. refer to the diagram showing global and member axes in "Coordinate Systems" on page 63. node/axis – angle between AC and AB too small This error message may be displayed in the output window during the checking phase prior to an analysis. When the structure type (as determined by the Structure > Type command) is plane truss or space truss. The member x axis is AB and the y axis is computed using the vector cross-product of AB and AC. Structures that are referred to as trusses are usually modelled as plane or space frames with member releases introduced as required. Microstran globally eliminates bending actions from the member stiffness formulation and every member behaves as if it is pin-ended. This situation. Apply restraints at all DOF where zero stiffness is reported. The structure is not fully triangulated. To understand what the error message means. in which case Microstran will automatically treat all members as pin-ended and delete rotational DOF. Using these structure types saves RAM but makes analysis more difficult for the user. If the angle is very small the computation is uncertain.
Any node in a space truss where all connected members lie in a plane is known as a coplanar node and will be unstable unless there is a restraint. This is sometimes the best approach for a preliminary analysis. instability or ill-conditioning will be reported during analysis. If the structure is fully triangulated. a tower structure modelled as a space truss (see "Example 3 – Space Truss" on page 349). releases may be inserted as required. Each face panel of the tower is a plane truss and although it may be stable in its own plane. below). bending moments will usually be insignificant but if they are not. out-ofplane displacement of the interior nodes of the truss must be inhibited to make the model stable. If it is not. a spring support. a zero stiffness error will occur if the plane is parallel to a global plane. This kind of modelling problem can be eliminated altogether by the use of rigid member offsets (see "Rigid Member Offsets" on page 94). While a value for the moment of inertia of the link of 10E3 times the moment of inertia of the column may yield satisfactory results. a value of 10E20 times that moment of inertia would cause ill-conditioning. warning messages are issued for all coplanar nodes detected. If the analysis proceeds with any instability of this type existing. Large Differences in Stiffness When very stiff structural elements are being modelled. when modelling a wide column.• • In a truss. unreasonably large values should not be input for section properties. a very stiff link member may be used to connect a node on the centre-line with a node on the face of the column. CONTINUOUS CHORD IN PLANE TRUSS Coplanar Nodes in Space Trusses In a space truss (where all members are pinned at both ends). the structure must be fully triangulated to be stable. or a master-slave constraint that inhibits displacement normal to the plane. For example. Remove all pins. Consider. Microstran V9 4:Structural Modelling • 77 . remove pins in the chord members (often continuous) leaving the web members pin-ended (see Case 2. In the Microstran checking phase. for example.
If the nodes of the column do not lie exactly on a vertical line (e. In such a case.Columns Without Rotational Restraint In a space frame where all beams connected to a column have moment releases about a vertical axis. Microstran may not detect a mechanism instability. Note: A beam with all connected members pinned creates a similar situation. there would be an excessively high condition number and there would be excessive rotation of the column nodes about the vertical axis. there will be a problem if the node at the base of the column does not have a rotational restraint about the vertical axis. COLUMN WITHOUT ROTATIONAL RESTRAINT Usually. the coordinates of one of the column nodes are slightly in error). 78 • 4:Structural Modelling Microstran V9 . This condition is illustrated in the model shown below. analysis will fail with a mechanism instability corresponding to rotation of the column about its axis.g.
Microstran V9 5:Structure & Load Data • 79 . The MLI format is similar to input formats used by some other structural programs including STRESS and STRUDL. Many configurations of portal frame may be input with the entry of a small number of parameters. The File > Import > Other command permits the input of data from some other program. With Macro Language Input the structure and load data are described in a text file. Table Input is a spreadsheet style of input that provides an excellent overview of the job in a tree view. regardless of the original input method. Double-clicking on any entity displays a table of all such entities. You may edit any job data by exporting the archive file. editing it with Microstran's text editor. You may copy to and paste from the Windows clipboard. CAD Input transfers structure data directly from any 3-D CAD system that uses the standard format AutoCAD DXF. Each data entity type is represented as a branch in the tree and you may expand any branch to show all the entities. Graphics Input is like a dedicated CAD system for entering structure and load data.5:Structure & Load Data Input Methods Microstran offers a variety of input methods that may be used interchangeably in any job. and design data for the job. such as Microsoft Excel. and then importing it back into Microstran. load. The archive file is a text file that contains all structure. The archive file format also provides the most convenient interface to Microstran for third-party programs. The data required is described in this chapter and the different input methods are discussed later. Structure data may also be transferred from Microstran to a CAD system. This input method is easy to learn and offers the greatest productivity in most situations. It is very useful when making changes. Powerful generation facilities make it an ideal method of input for many types of structure. so it is ideal for interfacing to spreadsheet programs. Standard Structures Input provides the quickest way to input many common types of structure. Archive File Input is the process of importing a text file of this type into Microstran.
tonnes. and °C. there is no need to renumber nodes and members. By default. Microstran uses units of meters. Any data extracted from section or material libraries will be converted automatically to the current units. Units The units of length. mass. and temperature used in a Microstran job may be determined by the user with the Structure > Units command.2) kip/g (386. Up to 60 characters of text are allowed in each line.0) Temp. you may enter this information with Microstran's text editor. MsEdit. There is no time or storage penalty when gaps occur in a numbering sequence. No. 1 2 3 4 5 80 • 5:Structure & Load Data Length meter (m) meter (m) millimeter (mm) foot (ft) inch (in) Force kilonewton (kN) newton (N) newton (N) kip (k) kip (k) Mass tonne (t) kilogram (kg) tonne (t) kip/g (32. Using the Structure > Designer's Notes command. On selecting the Structure > Units command a set of units may be chosen from the table below. which may contain any information desired. kilonewtons. appear on all output reports for identification of the job. force.Numbering Sequences Numbers are used throughout Microstran to identify structure elements such as nodes and members. Units are automatically converted if you select a set of units differing from that currently in effect. Designer's Notes Microstran associates descriptive information with each job. The job title may be entered with the Structure > Title command. These lines. Designer's notes are saved with the job data and are particularly useful for recording the development history of the job. °C °C °C °F °F Microstran V9 . If parts of the structure are added or deleted. Job Title Two lines of descriptive information may be entered for the job. These numbers are referred to as entity labels and they can be any integer from 1 to 99000.
Microstran V9 5:Structure & Load Data • 81 . 1 2 3 4 5 Type Plane truss in XY plane Grillage in XY plane Plane frame in XY plane Space truss Space frame Vert. In a plane or space truss all members are considered to have pinned ends. any loads or elastic restraints applied to suppressed degrees of freedom will be ignored. Grillages cannot have loads in the plane of the structure. When a structure type other than space frame is selected. the structure must be described as a frame. When you specify the structure type. Note: Plane truss and plane frame structures cannot have loads out of the plane of the structure. Microstran automatically reclassifies plane structures as space structures if any node coordinate is out of plane. grillages. Structure Type Microstran may be used to analyse plane trusses. Suppressed degrees of freedom (DOF) are shown in the table as . space trusses. Microstran will automatically apply the restraints necessary to enforce the restricted displacement pattern of the specified structure type. while remaining DOF are shown as . plane frames. No. not a truss. Y Z Y Any Any X Y Z RX RY RZ Restraints are applied to translations and rotations of the nodes with respect to the global axes. Structure type may be set with the Structure > Type command. If it is necessary for any member in a truss to be continuous (e. Additional restraints must be specified at support nodes.Note: All Microstran steel design options require the use of the meter and kilonewton units. chord members). and space frames.g.
The angular coordinate measured in degrees about the Z axis.Node Coordinates Node coordinates are defined with respect to a right-handed Cartesian (rectangular) axis system. Spherical Coordinates For each node whose coordinates are specified in spherical coordinates.Z) coordinates on input. See "Coordinate Systems" on page 63. referred to as the global coordinate system or the global axes. Global Z coordinate of node. GLOBAL COORDINATE SYSTEM Rectangular Coordinates For each node whose coordinates are specified in the global system. The angular coordinate (latitude) measured in degrees above the XY plane. in a righthanded sense from the X axis. Global Z coordinate of node. Cylindrical Coordinates For each node whose coordinates are specified in cylindrical coordinates. Two commonly used orientations of the global axes are shown in the diagram below. Global Y coordinate of node. the following values are required: X Y Z Global X coordinate of node. 82 • 5:Structure & Load Data Microstran V9 . the following values are required: R Θ Φ The radial coordinate of the node. Coordinates are automatically transformed by Microstran to global (X. The angular coordinate (longitude) measured in degrees about the Z axis. in a right-handed sense from the X axis. the following values are required: R Θ Z The radial coordinate of the node. Cylindrical and spherical axis systems may also be used in some input modules.Y.
Together with the longitudinal axis of the member. Node "B" – end of member. x. right-clicking. and computed member forces are specified with respect to the member axes. Section properties. The reference node or axis defines the orientation of the transverse member axes.e. provided it does not lie on the member x axis). If the node is used solely as a reference node it will be restrained automatically by Microstran. Except in the case of angle sections. such as having the x axis generally directed either upwards or to the right (as normally viewed). Reference Node Any node may be used for this purpose provided that it is not collinear with the member (i. some load types. See "Coordinate Systems" on page 63. and z. Each member has a set of axes. this will be achieved by using the default reference axis. x. in which the x axis is directed along the centroidal axis of the member from node "A" to node "B". also referred to as member incidence. In general. data input and interpretation of output are usually simplified if the member axes are oriented in a consistent manner. See "Coordinate Systems" on page 63. Microstran V9 5:Structure & Load Data • 83 . and choosing Properties on the context menu. Reference Node/Axis C Node/Axis "C" – reference node or axis. the y and z axes coincide with the principal axes of the member cross-section at "A". the xy plane usually coincides with the web plane of a member having an I-shaped crosssection. Key concept. As shown in the diagram. you may double-click on the member and change any of the values in the Member Property dialog box that is displayed. y. y and z. You can change properties of any number of members by selecting them. the reference node or axis defines a plane that contains the y axis. the principal axes of the cross-section coincide with the member y and z axes. Member connectivity.Member Definition As well as using toolbar buttons or the commands on the Structure > Attributes sub-menu to change any property of a member. is simply the specification of the two nodes joined by the member. Any value entered applies to all members selected. referred to as member or local axes. As a result. Member Connectivity A B Node "A" – start of member. Except in the case of angles.
-X.) Thus. Z. The default orientation of the member axes is shown for typical members in the diagram below. x. it is convenient to use a reference node at an extreme distance along that axis. and if so.Reference Axis For members with the member xy plane parallel to one of the global axes. is up or down. it may be used for all members with the same orientation. Vert. Microstran recognizes any of the six global axis directions (X. If a member is parallel to a global axis. (Because the dimensions of the structure subtend an infinitesimally small angle at this distant reference node. as commonly occurs in most structures. -Y. whether the member is vertical. a value will be assigned automatically. whether its longitudinal axis. -Z) as a reference axis. Axis X Y Z x Non Vert. that global axis must not be used as a reference axis for the member. Y. This value depends on the vertical axis of the structure. The default reference axis is set out in the table below for all relevant combinations of vertical axis and member x axis direction. Default Reference Axis If you leave any reference node/axis unspecified or input a "D". X Y Z x Up -Y -X -X x Down Y X X Each non-vertical member will have its y axis inclined upwards and each vertical member will have its y axis parallel to the horizontal global axis shown in the table. DEFAULT ORIENTATION OF MEMBER AXES 84 • 5:Structure & Load Data Microstran V9 .
Section Number Each member must be assigned a section number that appears in the list of sections in the input data for the structure – see "Section Properties" on page 88. Input Section No. each member in a framed structure has no releases and is connected rigidly to the adjacent nodes. Any combination of member releases may be used provided that the member remains stable and is not completely released from the structure at either end. The member release code consists of a string of six digits corresponding to the force components Fx. Fy. 000100 000100 111111 000000 Some member releases that occur in plane frames are shown below. By default. which are defined with respect to the member axes. pins) are used in framed structures to isolate a member from an adjacent node for one or more components of member force. Microstran V9 5:Structure & Load Data • 85 .Input Reference Node/Axis Use the Structure > Attributes > Reference Node/Axis command to set or modify the reference node/axis for one or more members. A torque release at each end would give rise to a member with no resistance to a torque applied to the member. Material Number Each member must be assigned a material number that appears in the list of materials in the input data for the structure – see "Material Properties" on page 92. Examples of unacceptable combinations are shown in the table below. A "1" means that a release DOES exist while a "0" means that is does NOT exist. Released member force components are zero. A code of 111111 at either end would result in the member being completely isolated from the adjacent node. Fz. and Mz. Use the Structure > Attributes > Section Number command to input the section number for one or more members. My. The default member release code is therefore "000000" at each end. Member releases must not be input when the structure type is plane truss or space truss.g. Member Release Codes Releases (e. Mx. Release Codes Problem 100000 100000 An axial release at each end would give rise to a member with no resistance to an axial load applied to the member.
Cross-Section Orientation Code For members whose cross-sections are not symmetrical about both principal axes. This is important for representing the structure accurately in rendered views. In the dialog box shown below. CROSS-SECTION DIRECTION CODE 86 • 5:Structure & Load Data Microstran V9 . the default orientation of the library sections for which this code is applicable is shown in the leftmost column. it is necessary to specify additional information so that Microstran can show the member with the correct cross-section orientation.MEMBER RELEASES Input Releases Use the Structure > Attributes > Member Releases command to input member releases for one or more members. When the first digit of the direction code is 1 it denotes rotation of the cross-section about the member y axis and when the second digit is 1 it denotes rotation of the cross-section about the member z axis. and also for the export of information to detailing programs.
Microstran V9 5:Structure & Load Data • 87 . Restraints are specified by the node restraint code. a string of six digits. Restraints are specified with respect to the global axes as shown in the following table.Fixed Supports (Node Restraints) A fixed support is created at a node when restraints are specified in one or more directions at the node. Loads applied directly at restraints are included in the calculation of reactions. A restraint should be specified in any direction for which a displacement is prescribed in the load data. Some node restraint codes that occur in plane frame structures are shown below. PLANE FRAME NODE RESTRAINTS Input Supports Use the Structure > Attributes > Fixed Supports command to input fixed supports at one or more nodes. Reactions at each restraint are listed in the reaction table in the analysis report. A "1" means that a restraint DOES exist while a "0" means that it does NOT exist. 1 X 2 Y Translations 3 Z 4 RX 5 RY Rotations 6 RZ Fixed support nodes are identified graphically with an arrow for translational restraints and a crossbar on the arrow stem for rotational restraints.
All stiffness values must be zero or positive – a zero value indicates that there is no spring in the corresponding direction. Section Properties For each job there is a table of sections. This permits all members with the same section number to be designed 88 • 5:Structure & Load Data Microstran V9 . Use the Structure > Attributes > Spring Supports command to input spring supports at one or more nodes. Translational spring stiffnesses are defined in units of force per unit displacement. If a fixed support and a non-zero spring stiffness are specified at any DOF. Nodes with spring supports are identified graphically by a spring symbol. for a rectangular section. Y translation spring stiffness. For example. Spring supports may be applied to any DOF that has not been suppressed because of the structure type. which is referenced by the section number specified for each member. • Microstran design options use the concept of a "design group". Sections may be input by any of the following methods: • • Library: Specifying the name of the section so that the properties may be extracted from a library. the moment required to produce an elastic rotation of one radian). Shape: Specifying the shape and the dimensions necessary for Microstran to compute the section properties.Spring Supports Spring supports are used to model external elastic supports provided by the foundation or other structures. the spring support will take precedence. They are defined by specifying up to six spring stiffnesses at each node where there is an elastic connection between the structure and a point of rigid support. Rotational spring stiffnesses are defined in units of moment per radian (i. X rotation spring stiffness. Y rotation spring stiffness.e. At each node where one or more spring supports exist. All spring stiffnesses act in the global axis directions and must be specified in consistent units. the following data is required: KX KY KZ KRX KRY KRZ X translation spring stiffness. the depth and breadth are input. Values: Entering directly the geometric properties of the section. Z translation spring stiffness. Z rotation spring stiffness.
You may edit libraries or make a new one using the File > Configure > Section Library Manager command (see Chapter 18 – "Section & Material Libraries"). If you wish to use this feature. Section Comment The comment is used to identify the section in reports. SECTION FROM LIBRARY Microstran V9 5:Structure & Load Data • 89 . whichever method is used: Section Name The section name is used to identify the section when extracting properties from a section library and also in reports. The following items of data may be input for each section. Up to 20 characters may be used.together. Up to 15 characters are allowed for the section name. you should allocate a different section number for each group of members having the same section. Use the Structure > Attributes > Section Properties command to choose a section number and input the properties for it. Input Section Properties Selection from Library To select a section from the configured library you only need to choose the section category and then the desired section. Standard naming conventions are used in Microstran section libraries. Blanks are not permitted.
SECTIONS AVAILABLE FOR SHAPE INPUT When entering section data by shape you may specify a moment of inertia factor. SECTION AXIS ALIGNED WITH MEMBER y AXIS Shape Input Often the most convenient input method for a section is to specify the shape and corresponding dimensions. The normally computed moment of inertia is multiplied by this factor. 90 • 5:Structure & Load Data Microstran V9 .g. m where m are used for node coordinates). the member y axis is directed upwards in each case.Section Axis Alignment For library sections you may specify the cross-section axis (XX or YY) that is aligned with the member y axis (see "Coordinate Systems" on page 63). Consistent units must be used for section dimensions (e. The shapes available are shown in the following diagram. In the diagram. It is typically used in reinforced concrete members to take account of reduction in stiffness caused by cracking.
. The following data is required: Cross-Sectional Area.g. however. A value of zero may be input if the members with this section are not required to withstand torque. m2 where m are used for node coordinates).e.g. Shear areas stored in section libraries are usually zero (i. Az The area that is effective in resisting shear distortion in the member z direction. J The St.SHAPE INPUT Property Value Input When property value input is selected. m2 where m are used for node coordinates). St. Microstran V9 5:Structure & Load Data • 91 . It must be in units consistent with those used elsewhere in the input (e. For I sections loaded in their strong direction the shear area is approximately equal to the area of the web. the geometric properties of each member cross-section are be specified numerically. you may change them by editing the library. Ay The area that is effective in resisting shear distortion in the member y direction. Shear Area. The shear area is required only if it is necessary to account for shear distortion. Venant torsion constant must be in units consistent with those used elsewhere in the input (e. Shear Area. See above.g. Shear distortions are usually a very small proportion of the total distortion of any member and are generally ignored in manual calculations. shear distortion is ignored). For solid rectangular sections it is equal to 5/6 of the cross-sectional area. shear distortions will be ignored in the corresponding members. In this case. Venant Torsion Constant. Ax The area must be in units consistent with those used elsewhere in the input (e. m4 where m are used for node coordinates). If you enter a value of zero. you should ensure that members with this section do not also have a torque release at either end.
Iz The second moment of area (moment of inertia) that is effective in resisting flexural distortion about the member z axis. Microstran is configured with a default material library name so that you will have to enter this only if you are not using the normal library. 92 • 5:Structure & Load Data Microstran V9 . The material library may be edited as required (see "The Material Library" on page 315). Material Name The material name is used to identify the material when extracting properties from a material library and also in reports.g. Blanks are not permitted. m4 where m are used for node coordinates Second Moment of Area. which is referenced by the material number specified for each member. or by entering directly the properties of the material. The material name may be input for each material. so that the properties may be extracted from a library. Use the Structure > Attributes > Material Properties command to choose a material number and input the properties for it.Second Moment of Area. Input Material Properties Selection from Library To select a material from a library you only need to specify the name of the library and the name of the material. Materials may be input by specifying the name of the material. Iy The second moment of area (moment of inertia) that is effective in resisting flexural distortion about the member y axis. NUMERICAL VALUES Material Properties For each job there is a table of materials. Up to 15 characters are allowed for the material name. whichever method is used. See above. It must be in units consistent with those used elsewhere in the input (e.
Typical values for steel and concrete are 7.7E-6 per °C is typically used for both steel and concrete. where meters and kilonewtons are used. Use the Structure > Attributes > Node command to input node mass at one or more nodes.15 or 0. the mass of each member is automatically computed and assigned to the nodes at the ends of the member.5 × E / (1 + µ) Typical values are 0. Coefficient of Thermal Expansion The coefficient of thermal expansion is only required if thermal loads are applied to the structure.85 t/m3 and 2. for example. and time units: If m and kN are being used. material mass densities should be in t/m3.20 for concrete. respectively. The unit used for mass must be consistent with the force. Microstran V9 5:Structure & Load Data • 93 . the properties of each material are specified numerically.Property Value Input When property value input is selected. Accelerations specified in static analysis will not result in inertial loads being applied at nodes where mass has been input.25 for steel and 0. µ Poisson's ratio is used to compute the shear modulus from the expression: G = 0. Node mass input is only relevant in dynamic analysis. the unit of mass will be the tonne. kN/m2 – kilopascals – where m and kN are used). Mass additional to that of the frame may be input at any node. Mass Density The mass density is required for the calculation of acceleration loadings and the structure mass.5 t/m3. The following data is required: Young's Modulus.g. Node Mass In dynamic analysis. The units must be consistent with those used elsewhere in the input. Poisson's Ratio. length. A value of 11. E Young's modulus must be in units consistent with those used elsewhere in the input (e.
Z offset from node "A" to end of member. Where members meet at the joints in a structure. This is the "joint block" region. Y offset from node "B" to end of member. Z offset from node "B" to end of member. If the member cross-section dimensions are large. from the node to the end of the member. The following data is required: dXA dYA dZA dXB dYB dZB X offset from node "A" to end of member. RIGID MEMBER OFFSETS Rigid member offsets may be input using the Structure > Attributes sub-menu.Rigid Member Offsets If designing a structure under steel design code rules for "simple construction" you must use rigid member offsets. X offset from node "B" to end of member. the very stiff joint block region may be relatively large. there may be little distortion in the part of the structure that is common to more than one member. The connection between the node and the rigid member offset is rigid. Y offset from node "A" to end of member. Any releases specified for the member will be inserted between the end of the member and the rigid offset. The diagram below shows typical applications of rigid member offsets. When rigid member offsets are used to model the joint block region the end of the member is considered to be connected to the adjacent node by an infinitely rigid link. Similarly. The extent of each rigid member offset is input by specifying the distance. not at the node. if a semi- 94 • 5:Structure & Load Data Microstran V9 . measured in either the global or local axis directions.
All load offsets are measured from the "A" end of the member as shown in example (1) in the diagram above. The following data is required: Microstran V9 5:Structure & Load Data • 95 . Many rigid member offsets are simply extensions of the member centre-line but they do not have to be. springs will be inserted between the end of the member and the rigid offset. Loads can be applied to the flexible part of the member only. The spring stiffnesses are specified with respect to member axes and may be entered independently at each end. You may model this situation with semi-rigid connections. Note: The orientation of the local axes used for specifying offsets may be changed by the offsets. Any member for which semi-rigid connections are specified is considered to have axial and rotational springs inserted between the end of the member and the adjacent node or rigid offset. The diagram below shows how rigid member offsets are specified with respect to the global axis directions.rigid connection is specified adjacent to a rigid member offset. where beams are aligned in plan with the faces of columns. RIGID MEMBER OFFSETS SPECIFIED IN GLOBAL AXES Semi-Rigid Connections In some structures there may be partial continuity between the ends of a member and the adjacent nodes. the rigid offset will be cranked as shown in example (3) above. which may be input using the Structure > Attributes sub-menu. For example.
This feature lets you impose relationships between displacement components at different nodes. Master-Slave Constraints You may input master-slave constraints using the Structure > Attributes sub-menu. Spring constant at "A" for rotation about member z axis. Sometimes. in-plane DOF are not required for each slave node because the three components of displacement in the horizontal plane can be determined from the in-plane displacements of the master node. Note: Ill-conditioning will result if a very large value is used to specify an "infinite" stiffness – input "R" to denote a rigid connection DOF. One node on the floor is specified as the master node and all other nodes at that level are slaves for the in-plane DOF. Spring constant at "A" for rotation about member y axis. In effect.KxA KRyA KRzA KxB KRyB KRzB Spring constant at "A" for displacement along member x axis. Master node for Z translation of slave node. Master node for Y translation of slave node. Master node for RZ rotation of slave node. 96 • 5:Structure & Load Data Microstran V9 . Spring constant at "B" for rotation about member y axis. Master node for RY rotation of slave node. Displacement components at a slave node may be constrained to conform to those of other nodes. Spring constant at "B" for displacement along member x axis. friction joints can be modelled approximately by using appropriate spring constants (possibly determined from tests). The master node number is specified for each of the selected slave nodes: MNX MNY MNZ MNRX MNRY MNRZ Master node for X translation of slave node. A pinned connection has a spring constant of zero and a rigid connection has a spring constant of infinity. One of the main applications of the master-slave feature is in modelling floors considered to be rigid in their own plane. The diagram above shows the locations of the spring elements for a member that has rigid offsets. An error will be reported if a member contains a pin and a semi-rigid connection at the same end. designated master nodes. Master node for RX rotation of slave node. Spring constant at "B" for rotation about member z axis.
Loads may be applied at slave DOF. the deletion of members in which the axial force would exceed the Euler load can also cause a structure to be unstable.e. Compression-only members may be used to model supports where "liftoff" occurs under some conditions. both bracing members would be deleted. Note: During non-linear analysis. the deletion of a tension-only or compression-only member will cause a structure to become unstable. Master DOF may not be slaves to any other DOF. or elastic). tension-only members may be used to model compression-only elements (and vice versa). The following rules apply to master-slave constraints: • • There may be any number of master nodes. The number of DOF in the analysis is reduced by the number of constraint relationships.Set the master node number to zero if the corresponding DOF is not constrained. (A master node may appear as a slave node provided that the DOF specified as masters are not themselves slaves). Sometimes. • • The node displacements and member forces are reported for slave nodes. in the structure shown below. For example. Tension-Only & Compression-Only Members Members may be marked as tension-only or compression-only using the Structure > Attributes > Member Type command. For large structures this may result in some savings in the size of the structure stiffness matrix and in the time required for solution. the member is ignored). As shown in the diagram below. the axial extension of these members is checked at each iteration and if it is found to be inconsistent with the specified member type. See "Troubleshooting Non-Linear Analysis" on page 254. causing the structure to be unstable. A simple solution to this particular problem is to apply a horizontal load to produce a small tension in one bracing member or to preload both with a small tension (as would probably occur in practice). During non-linear analysis. Microstran V9 5:Structure & Load Data • 97 . Note that any eliminated member may be reinstated in subsequent iterations. the stiffness of the member is set to zero for the next iteration (i. Tension-only members are often used to model "X"-bracing members that are so slender that they can support negligible compression. Slave DOF may not be specified as supports (fixed.
Cable members may be subjected to acceleration loads. may be specified for each cable member. the unstrained length. Cable members have axial tension only – no other member force components exist. Member end releases are not permitted in cable members. The initial tension determined by the unstrained cable length is taken into account automatically. uniformly distributed loads in any global axis direction. Global displacement values for a cable are shown in the analysis report when appropriate options are selected. Note: When using the Query > Member Displacements command the global values tabulated in the output window for a cable are not displacements. using the Structure > Attributes > Member Type command. 98 • 5:Structure & Load Data Microstran V9 .TENSION-ONLY BRACING Cable Members When this advanced option is available the member type may be set to cable. The catenary formulation of the cable element permits the accurate computation of the equilibrium position of each cable under load. On input. temperature loads. and axial distortions. which defaults to the chord length. but coordinates of the displaced cable. The sag is also shown. Additional nodes may be introduced within cables if it is necessary to apply concentrated loads. Variation of the unstrained length changes the initial tension of the cable.
Gap & Fuse Members
When this advanced option is available the member type may be set to gap, brittle fuse, or plastic fuse, using the Structure > Attributes > Member Type command. During non-linear analysis, the behaviour of these members is determined as a function of extension or internal axial force. Gap and fuse members in compression do not buckle. Fuse members have a moment release at each end.
Gap Member
Gap members may be used to model situations where one part of a structure bears on another after a certain relative displacement. Member properties include two non-negative values, a compression gap and a tension gap. The compression gap is the amount by which the node-to-node distance may shorten before any compression is induced and the tension gap is the amount by which this distance may lengthen before any tension is induced. A slotted member, whose behaviour can be modelled by the gap member, is shown below.
As the member extension goes beyond either limit the axial force in the gap member increases linearly from zero at the limit. The diagram below shows an axial force-extension graph for a gap member compared to that for a similar normal member.
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Brittle Fuse Member
Brittle fuse members may be used to model members that fail in a nonductile manner (e.g. by rupture or buckling) at a specified limiting axial force. Member properties include two non-negative values, a maximum compressive force and a maximum tensile force. In a brittle fuse member the axial force becomes zero if axial compression reaches the maximum compressive force or if axial tension reaches the maximum tensile force. In the brittle fuse member the internal axial force becomes zero after it has reached either limiting value. Brittle fuse members cannot buckle. Note: You may use a fuse member with large values for Pcomp and Ptens to model members that cannot buckle. The diagram below shows an axial force-extension graph for a brittle fuse member compared to that for a similar normal member.
Plastic Fuse Member
Plastic fuse members may be used to model members that fail in a ductile manner at a specified limiting axial force (i.e. an elasto-plastic member). Member properties include two non-negative values, a maximum compressive force and a maximum tensile force. In the plastic fuse member the internal axial force remains constant after it has reached either limiting value. Plastic fuse members cannot buckle.
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The diagram below shows an axial force-extension graph for a plastic fuse member compared to that for a similar normal member.
Note: Analysis of structures containing gap or fuse members may fail if the structure becomes unstable when a member of this type loses its axial stiffness. You may be able to overcome this kind of problem by use of the displacement control analysis parameter or by adding very flexible springs or dummy members to keep the structure stable while gap members are not resisting axial force.
Load Case Titles (CASE)
The load data for a job consists of one or more primary load cases and optional combination load cases. Each load case is identified by a unique load case number. The load case number is used for the selection of load cases throughout the Microstran system – in the plotting, reporting, and design modules and for the definition of load combinations. If a load case is deleted, you must ensure that no remaining combination load case refers to it. Each load case is described with a line of up to up to 50 characters of text. This title is used to identify the load case in reports and graphical output. Click the New Load Case button or select the Loads > Add Case / Edit Title command to input the name of a new load case or change the name of an existing load case.
New Load Case
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Acceleration Loads (GRAV)
Acceleration or gravitational (GRAV) loads are caused by the effects of acceleration or a gravitational field acting on the mass of the structure. Microstran computes acceleration forces in each global axis direction for each member as the product of the mass of the member and the respective component of acceleration.
GX GY GZ Global X component of acceleration. Global Y component of acceleration. Global Z component of acceleration.
Accelerations must be in units consistent with those used elsewhere in the input. Structure self-weight may be taken into account by specifying an acceleration of –g in the vertical axis direction. For example, if m and kN units are being used, you would specify a value of -9.81 m/sec2 for the acceleration component in the Y direction (assuming that the global Y axis is the vertical axis). After selecting an input load case, you may input an acceleration load using the Loads > GRAV Load command to specify the acceleration components. The input load case is selected by choosing it in the Current Input Case drop-down list box or you may use the Loads > Select Input Case command. Note: The GRAV load does not create inertial loads for the additional mass usually input for dynamic analysis.
Node Loads (NDLD)
Node loads are loads applied directly to the nodes of the structure. The load on each loaded node is defined by the components of force and moment in the global axis directions.
FX FY FZ MX MY MZ Force acting in X direction. Force acting in Y direction. Force acting in Z direction. Moment acting about X axis direction. Moment acting about Y axis direction. Moment acting about Z axis direction.
The applied force components are positive when acting in the direction of the global axis. The applied moment components are positive when acting clockwise about the global axis (as viewed along the axis).
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Positive node forces and moments are shown in the diagram below.
Input Node Loads
After selecting an input load case, you may input node loads by clicking the Input Node Loads button or selecting the Loads > Node Loads command to specify the load components. You may also right-click on a node and choose Edit Node Loads from the context menu. The input load case is selected by choosing it in the Current Input Case drop-down list box or you may use the Loads > Select Input Case command.
Member Loads (MBLD)
Concentrated and distributed forces and couples may be applied at any point in a member. Each member load is specified by the form of the load and parameters describing the intensity and location. Loads may be defined with respect to either the global or the member axes. Where the member has rigid offsets load distances are measured from the end of the member, not the node.
Load Form
A four character mnemonic to define the form of the load:
CONC TRAP UNIF TRI1 TRI2 Concentrated (point) load. Distributed load over part or all of the member whose intensity may vary linearly. Distributed load of uniform intensity over the full length of the member. Triangular distributed load with zero intensity at the ends of the member ends and maximum at the midpoint. Similar to TRI1 but with the apex symmetrically truncated.
The different forms of member loads are shown in the diagram below.
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Load Type
A two-character mnemonic to define the load as a force or couple and specify the direction of its action.
FX FY FZ MX MY MZ Force acting in X direction. Force acting in Y direction. Force acting in Z direction. Moment acting about X axis direction. Moment acting about Y axis direction. Moment acting about Z axis direction.
The applied force components are positive when acting in the direction of the associated axes. The applied moment components are positive
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when acting clockwise about the associated axis (as viewed along the axis).
Load Axes
A two-character mnemonic to define the axis system in which the load is described.
GL LO The direction of the load is referred to a global axis. Direction of the load is referred to a member (local) axis.
Load Scale
A two-character mnemonic to define the method of specifying offsets from the "A" end of the member to the load reference points.
LE FR Offsets are in length units. Offsets are fractions of the member length.
Load Parameters
F1 X1 F2 X2 Load intensity (load per unit length) at the first reference point, or the magnitude of a concentrated load. Offset (measured along the member) from end "A" of the member to the first reference point. Load intensity (load per unit length) at the second reference point. Offset (measured along the member) from end "A" to the second reference point.
Not all of the above parameters are required to describe some load forms. The load forms and the parameters required to define them are shown in the diagram above. The loadings shown are general and may represent forces or moments acting in the direction of any of the global or member axes. The Member Load dialog box allows you to specify offsets measured from the "B" end of the member. However, offsets are stored internally and represented in the archive file as offsets from the "A" end of the member. After selecting an input load case, you may input member loads by clicking the Input Member Loads button or selecting the Loads > Member Loads command.You may also right-click on a member and choose Input Member Loads from the context menu. The input load case is selected by choosing it in the Current Input Case drop-down list box or you may use the Loads > Select Input Case command.
Input Member Loads
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25 . The member load entries required to define these loads are also shown. Some loads may be described in either the global or member axis systems and it is advisable to use whichever is more convenient. loads should be 106 • 5:Structure & Load Data Microstran V9 .25 .092 .25 3.277 or MBLD MBLD Load B: or MBLD MBLD Load C: or MBLD MBLD MBLD Load D: Load E: or MBLD Member loads may be defined in a variety of ways.25 3. Where possible.5 -15 -15 .092 . Each load is represented by a line of data starting with "MBLD". This is the format used to describe loads in the archive file.Member Load Example Some member load examples are shown in the diagram below. MEMBER LOAD EXAMPLES Load A: MBLD 1 CONC FY LO FR 1 CONC FY LO LE 1 TRAP FY GL FR 1 TRAP FY GL LE 3 TRI2 FY LO FR 3 TRI2 FY GL FR 3 CONC MZ LO FR 2 UNIF FY LO 2 UNIF FX GL -20 -20 -10 -10 -8 -8 12 -5 5 .75 9.
Transverse discontinuity parallel to z axis. These may be used to model "lack of fit" or prestress. Offset from end "A" of the member to the location of the discontinuity. in the form of linear or angular discontinuities. Microstran V9 5:Structure & Load Data • 107 . Transverse discontinuity parallel to y axis. influence lines can be made for a structure by plotting the distorted shape of the structure with a unit distortion applied at the point where the influence is required. Angular discontinuity – rotation about x axis. Each distortion is specified as a member load of form DIST. may be introduced at any point in a member. However.input with respect to the global axes because the load direction is then evident without reference to member axis orientation. The parameters required to specify the distortion are listed below. The Member Load dialog box allows you to specify offsets measured from the "B" end of the member. Angular discontinuity – rotation about z axis. LE FR Offsets are in length units. By the Müller-Breslau Principle. Angular discontinuity – rotation about y axis. Fractional scaling is particularly useful where loads occur at easily defined intermediate points such as the midpoint or the third-points of the member. Offsets are fractions of the member length. Distortion Scale A two-character mnemonic to define the method of specifying the location of the discontinuity. offsets are stored internally and represented in the archive file as offsets from the "A" end of the member. Distortion Parameters F1 X1 Magnitude of discontinuity in length units for linear distortions and radians for angular distortions. Distortion Type A two-character mnemonic to define the distortion as a linear or angular discontinuity and specify its direction: FX FY FZ MX MY MZ Axial discontinuity. Member Distortions (DIST) Member distortions.
you may input member distortions using the Loads > Member Loads command. MEMBER DISTORTIONS 108 • 5:Structure & Load Data Microstran V9 . You may also right-click on a member and choose Input Member Loads from the context menu. Some commonly used distortions and the parameters required to define them are shown in the diagram below. The illustrated distortions are all in the positive sense.After selecting an input load case. The input load case is selected by choosing it in the Current Input Case drop-down list box or you may use the Loads > Select Input Case command.
Every member connected to a node where a temperature differential has been input will be subjected to a constant temperature gradient. If the structure is statically indeterminate thermal expansion will be restrained and thermal stresses will result. The input load case is selected by choosing it in the Current Input Case drop-down list box or you may use the Loads > Select Input Case command.Node Temperatures (TEMP) A temperature differential may be specified at any node in the structure. you may input node temperatures using the Loads > Node Temperatures command. Microstran V9 5:Structure & Load Data • 109 . Temperatures must be in units consistent with those used for the coefficient of thermal expansion. In a statically determinate structure the member is free to expand and displacement will occur without the development of any thermal stresses. The temperature differential varies linearly along the member between the values at the end nodes. The temperature differential is the increment of temperature above or below the temperature at which no thermal stresses occur. NODE TEMPERATURES After selecting an input load case.
If the temperature gradient is linear over the cross-section. Tx will be the temperature differential at the centroid of the section. Ty Tz The function T(y.z) describes the temperature variation over the crosssection of the member.Member Temperatures (MTMP) Member temperature gradients may be input to describe the variation of temperature across the member cross-section. If the member is unrestrained. The effective temperature gradient across the member in the z direction. 110 • 5:Structure & Load Data Microstran V9 . it causes curvature about the z axis. MEMBER TEMPERATURE GRADIENT After selecting an input load case. If the member is unrestrained. It is assumed that this is constant for the full length of the member. the effective temperature gradient is the difference between the temperatures of the extreme fibres divided by the depth of the section. The effective temperature gradient across the member in the y direction. The input load case is selected by choosing it in the Current Input Case drop-down list box or you may use the Loads > Select Input Case command. it causes curvature about the y axis. For rectangular sections and linear temperature gradients. you may input member temperatures using the Loads > Member Temperatures command. Tx Average temperature differential of the member. It is assumed that the temperature profile of the cross-section is constant along the length of the member.
i. Microstran V9 5:Structure & Load Data • 111 . or Z axes respectively (as viewed along the axis). DX DY DZ RX RY RZ Translational displacement in X direction.Prescribed Node Displacements (NDIS) Prescribed displacements are often used to model settlement of supports. Node displacements may be specified in one or more directions at any node. Such prescribed node displacements are defined by giving the components of translation and rotation in the global axis directions. Translational displacement in Z direction. The input load case is selected by choosing it in the Current Input Case dropdown list box or you may use the Loads > Select Input Case command. you may input prescribed node displacements using the Loads > Node Displacements command. or Z axes respectively. PRESCRIBED DISPLACEMENTS After selecting an input load case. Y. Positive translational and rotational displacements are shown in the diagram below. Y. The translation components are positive when in the direction of the global X. Rotational displacement about Z axis direction. Rotational displacement about Y axis direction. Any DOF where a displacement is prescribed must be defined as a support. The rotational displacement components are measured in radians and are positive when clockwise about the global X. Translational displacement in Y direction. a "1" must be entered into the node restraint code for that DOF. Rotational displacement about X axis direction.e.
ALL MEMBERS SELECTED In this diagram some members were not selected for the application of the area loading. whether overlapping or not. because the area enclosed by the outer loop of selected members is the same. the total area load is the same. Area loading may be applied simultaneously to several floors or frames. Nevertheless. Loads are not applied to members perpendicular to the load direction. The diagram below shows all members of a grillage selected for the application of an area load and the resulting loads on the members forming the grillage. Note: Area loads cannot be applied to any set of members where members cross without intersecting. The tributary area is determined by the outer loop of the selected members.Area Loading Microstran permits the application of a load uniformly distributed over a selected area. 112 • 5:Structure & Load Data Microstran V9 . The load is specified as a force per unit area and it is applied as a number of statically equivalent distributed loads on the selected members.
The area load must be applied in two steps with the outer loop of selected members in each case not enclosing the opening. VOID EXCLUDED FROM TRIBUTARY AREA Area Loading After selecting an input load case. The input load case is selected by choosing it in the Current Input Case drop-down list box or you may use the Loads > Select Input Case command.THE SAME TRIBUTARY AREA The diagram below illustrates how an area load may be applied to a grillage so that a void is not included in the tributary area. Microstran V9 5:Structure & Load Data • 113 . you may input area loading by clicking on the Area Loading button or selecting the Loads > Area Loading command.
The factor by which the specified load case is multiplied before being added to the current combination load case. type "C"). the load case number and a factor. Load case number. 114 • 5:Structure & Load Data Microstran V9 . Factor Multiplier for load case. Component load cases may be either primary load cases or other combination load cases.e. The input load case is selected by choosing it in the Current Input Case dropdown list box or you may use the Loads > Select Input Case command. You cannot input combination components unless the selected load case is a combination load case (i. you may input the combination components by clicking on the Input Combination Case button or selecting the Loads > Case Combinations command. Case No. and for each component load case. a title.Combination Load Cases (COMB) Each combination load case requires a load case number. The case number of each component must be less than the current case number. The number of a primary or combination load case. Input Combination Case After selecting an input combination load case.
81 0 101 UNIF FY GL -10 102 UNIF FY GL -10 103 UNIF FY GL -10 104 UNIF FY GL -10 2 LL 101 102 103 104 UNIF UNIF UNIF UNIF FY FY FY FY GL GL GL GL -20 -20 -20 -20 CASE 11 1.ltp.5*LL COMB 1 1. After installation from the CD there should be at least one sample load case template file available. Any existing load cases that do not conflict with the template remain unchanged.9 END The load case template is activated for any existing job with the Loads > Import Load Case Template command.5 CASE 12 .9*DL COMB 1 .Load Case Templates A load case template can save time setting up the load cases in a model.2*DL + 1.2 COMB 2 1. You may store a standard set of loads in a load case template and import it into any model to define or add to the load cases. Load case template files reside in the Microstran \Lib folder and have an extension of . An existing load case having a case number defined in the template is totally replaced by the template load case. Microstran V9 5:Structure & Load Data • 115 . A typical load case template file is shown below: CASE GRAV MBLD MBLD MBLD MBLD CASE MBLD MBLD MBLD MBLD 1 DL 0 -9. Use the File > Configure > Edit Load Case Template command to edit an existing template or make a new one.
sub-dividing a member into a curve. extrusion.6:Graphics Input General Graphics Input is the most efficient input method in many situations. GRAPHICS INPUT Many Microstran users have found that the few hours required to become proficient at graphical input have been be well rewarded by vastly increased productivity in most aspects of structural analysis and design. Important Note: It is essential that you understand the material in Chapter 2 – "Getting Started" before you can use Graphics Input effectively. moving. A good way to learn Graphics Input is to work through some of the examples in Chapter 12 – "Tutorials". It involves "drawing" a structure on the screen using the mouse or keyboard. and erasing. such as copying. In effect. More powerful graphical operations include intersection. Microstran's graphical input capability is a CAD system customized for the task of entering structure and load data. Microstran V9 6:Graphics Input • 117 . and it includes many simple graphical operations. rotating. sub-dividing. and transforming coordinates.
You may continue selecting points to define new members. Refer to "The 118 • 6:Graphics Input Microstran V9 . You may now click anywhere in the main window or enter coordinates from the keyboard to locate the "A" node of the first member.Undo / Redo Undo restores the job to its status immediately before the last command. A typical example is shown below. This point is the "B" node of the first member and the "A" node of the next member. press SPACE BAR to break line". A help window. As you initiate the Draw command several things happen: 1. click on the button. The cursor becomes a cross. It is particularly useful if incorrect data is input in one of the more complex drawing commands. Notice the tooltip "Draw Members" that appears when the mouse cursor crosses this button. Redo reverses the effect of the Undo command when selected immediately afterwards. This is the same as selecting the Structure > Draw Members command from the menu bar. The toolbar button displays in the depressed state. appears (see above). The prompt area of the status bar (on the left) displays the instruction "Click on first point or enter coordinates". indicating that Microstran is in DRAW mode. THE COMMAND ASSISTANT Basic Drawing Click on the toolbar button to show the grid and then. to start drawing a structure. the Command Assistant. Notice that once the first point is specified the prompt changes to "Click on end point or enter coordinates. When you no longer require the Command Assistant you may turn it off from the Help menu. 3. "DRAW" is displayed in the status bar at the bottom of the Microstran window. 5. Select another point and you will have drawn the first member. 4. 2. The Command Assistant The Command Assistant is a special help window that appears automatically to provide additional information for many drawing commands.
and height of the point. For example. and "phi" are • • Microstran V9 6:Graphics Input • 119 . the X. DIALOG BOX FOR ENTERING COORDINATES Coordinate Systems You may input coordinates in rectangular. and "h" are respectively. horizontal angle. the radius.Drawing Snap Mode" on page 120 for information on changing the snap mode. or spherical coordinate systems. Keyboard Entry of Coordinates Key concept. "theta". the radius. No separator is required after the "R" or "r". where "radius". The last two values must be separated by a space or a comma. "Y". where "X". where "radius". "Y". and Z coordinates of the point. Y. "theta". Coordinates relative to the last point are preceded by "R" or "r". "theta". the X. and "Z" are respectively. As soon as you start to type. where "radius". a dialog box appears to accept your input. AUTOCAD SYNTAX • Rectangular coordinates "X Y Z". and "phi" are respectively.0. • • Trailing zero coordinates do not have to be entered. and "Z" are respectively. Spherical coordinates "radius < theta < phi". where "radius". STANDARD SYNTAX • Rectangular coordinates "X Y Z". the radius. horizontal angle. and "h" are respectively. Cylindrical coordinates "radius < theta h". cylindrical. using standard syntax or AutoCAD syntax. "theta". The format of the coordinate string is described below for each syntax. where "X". Coordinates must be separated by a space or a comma. There are many situations where the most convenient way to enter a new node is to type the coordinates. Spherical coordinates "S radius theta phi".0) may be entered as "3". Y. and height of the point. Cylindrical coordinates "C radius theta h". the point (3. and vertical angle of the point. horizontal angle. and Z coordinates of the point.
When starting a new structure you cannot enter Mid/End snap mode because there are no members to snap to. The Drawing Snap Mode Key concept. When starting a new structure you cannot enter Intersection snap mode until there are at least two members. Thereafter. No separator is required after the "@". A new node is automatically introduced at the intersection point if there is not already a node there. Initially. Grid spacing is initially 1 unit in each global axis direction but you may change it with the Structure > Drawing Settings > Grid Spacing command. The status bar and the button also show that Microstran is no longer in Draw mode. Mid/End Snap Mode (MEND) When drawing in this mode the cursor snaps to a nearby member end or mid-point. Notice that the cursor. Enter coordinates to specify a point that is not on the grid. Notice the cursor change to the standard arrow. Most graphical input is done in this snap mode. Ending the Line Hit the "End" button or right-click and choose End Line on the context menu. Grid Snap Mode (GRID) In Grid mode the status bar displays GRID. the status bar. Intersection Snap Mode (INTR) When drawing in this mode the cursor snaps to a nearby intersection of two or more members. with the mouse. Breaking the Line Press the space bar or right-click and choose Break Line on the context menu. and vertical angle of the point. you can only draw members from one grid point to another. When the grid is displayed the cursor snaps to the nearest grid point. the Mid/End snap mode is mostly used. the radius. You may now click a new node that is not connected to the last by a member. Thus.respectively. Perpendicular Snap Mode (PERP) 120 • 6:Graphics Input Microstran V9 . The first few nodes are usually specified by grid points or entry of coordinates. This means that the coordinates of any node defined by clicking the mouse will be determined by the exact mouse position. The degree of accuracy with which you can position the mouse is limited so the snap mode NONE is rarely used. the status bar displays NONE for the snap mode. horizontal angle. This indicates that the command is finished. and the button show that Microstran is still in Draw mode. Coordinates relative to the last point are preceded by "@".
When starting a new structure you cannot enter Perpendicular snap mode until there is at least one member. Microstran V9 6:Graphics Input • 121 .In this mode the cursor snaps to the point on a target member that makes the new member perpendicular to the target member.
Shortcut keys are also known as accelerator keys. pressing Delete usually deletes selected members.Orthogonal Snap Mode (ORTH) In this mode you can only draw members in a global axis direction. Microstran's shortcut keys are listed below: Main View Shortcut Command Viewpoint left * Viewpoint right * Viewpoint up Viewpoint down Page Up Ctrl+C Ctrl+X Ctrl+V Ctrl+Z Ctrl+Y F5 Ctrl+A Delete Home Esc Enter Space 122 • 6:Graphics Input Zoom in Copy Cut Paste Undo Redo Redraw Select all Erase members Zoom to extents/limits Cancel Confirm or OK Break Line Microstran V9 Page Down Zoom out . Right-click to display the context menu with its selection of snap modes (see diagram at the beginning of this chapter). For example. The effect of pressing a shortcut key depends on the context. you may click the start point of a new member at the end of another while in Mid/End snap mode and then change to Grid snap mode to select the end point. but in a dialog box it may delete text or do nothing. Shortcut Keys Microstran permits the use of shortcut keys to some commands. Changing the Snap Mode "On the Fly" A very convenient feature is the ability to change the snap mode during a draw operation. Nearest Snap Mode (NEAR) In this snap mode the cursor snaps to the point on a target member that is nearest to the cursor location. For example.
* May be configured to rotate structure instead of moving viewpoint. Graphics Input Shortcut Command D E M L P R O S 2 3 Draw members Erase members Move members Linear copy Polar copy Reflect members Rotate members Sub-divide members Sub-divide members into two Sub-divide members into three Graphics Input while in Draw Mode Shortcut Command M G I O P Space End Middl/end snap mode Grid snap mode Intersection snap mode Orthogonal snap mode Perpendicular snap mode Break line End line OpenGL (Virtual Reality)View Shortcut Command Viewpoint Left * Viewpoint Right * Viewpoint Up Viewpoint Down Page Up O S N M Zoom In Show global axes Show node symbols Show node numbers Show member numbers Page Down Zoom Out Microstran V9 6:Graphics Input • 123 .
The first node or member to be drawn will remain and any that are superimposed will be removed automatically. Microstran removes any duplicate nodes or members that are detected. Left View. Use the Structure > Drawing Settings > Drawing Plane command to change the drawing plane as required. or Top View commands automatically changes the drawing plane so that it is parallel to the view plane. the drawing plane is X-Y at an offset of zero along the Z axis. If you change the view or the drawing plane so that it (the drawing plane) is at right angles to the view plane (the plane of the screen) you may see the warning message shown below and you may not be able to click a new point. Right View.JPG image file Print image Revert to initial view * May be configured to rotate structure instead of moving viewpoint. when drawing in Grid snap mode with default settings. The Drawing Plane The drawing plane is a plane on which nodes are located when you draw in either the Grid or NONE snap modes. WARNING THAT DRAWING PLANE IS PERPENDICULAR TO SCREEN Automatic Removal of Duplicate Nodes and Members At various stages during graphical input operations. Key concept. This means that all new nodes drawn in Grid or null snap mode have a Z coordinate of zero. 124 • 6:Graphics Input Microstran V9 .L X C F R J P Esc Show steel design restraints (LTB) Show connection symbols Show connections Show connection status flags Reverse connection status flags Save . For example. Changing the view with any of the Front View. Back View.
EXTRUSION OF NODES Interrupting Commands Most commands may be interrupted by clicking a button on theView toolbar.Extrusion Key concept. There will be a new cross-beam. below. The diagram below illustrates this procedure. or pan the view. when drawing a member. When you perform a copy operation you may "extrude" each copied node into a series of members – in other words. together with connected girders (longitudinal) for every copy. sub-dividing it as required to create a node at the location of each girder. and then performing a polar copy with extrusion. VIEW TOOLBAR You may also interrupt commands by clicking buttons on the Display toolbar. as required. There is a check box for "Extrude nodes" in each of the Linear Copy. and the view required for displaying the "B" node is different from that in which the "A" node is visible. Polar Copy. shown below. For example. zoom in to a congested area of the model. Extrusion is a powerful feature that enables you to create many types of structure with minimal effort. You may interrupt graphical commands to rotate the view. there will be a string of new members lying on the path traced out by each node involved in the copy operation. The member x axis is aligned with the direction of extrusion. you can make a curved bridge deck model by drawing a member representing a cross-beam at one end. for example. This is helpful in many situations. DISPLAY TOOLBAR Microstran V9 6:Graphics Input • 125 . and Reflect dialog boxes.
. you must either click a point with the mouse or enter the coordinates of a point that. together with the end nodes of the member..The Curve Command If you complete a curve command that does not have the desired effect you may . if any of these nodes are coincident with existing nodes they will be merged with them. and. This point does not have to be the centre of the arc but it must lie on the same side of the arc as the centre. The effect of this is that members connected to the pre-existing coincident nodes will be "stretched" so they remain connected to the curved member. When you see the prompt. vertical web members remain vertical after the operation. defines the plane of the arc. click the Undo button. Click on point on plane of arc or enter coordinates. Equal segments on the chord is the option normally required when curving a chord of a truss – in this case.. CURVE MEMBERS DIALOG BOX Selecting equal segments on the arc will create new members that are equal in length. if curving a horizontal member into an arch. At this stage. the point must be below the member in the plane of the arch.. This is illustrated in the example below. You may select one or more members for this command. 126 • 6:Graphics Input Microstran V9 . when 5 are selected. The sub-division of the member in the Curve command introduces new nodes that are initially on the chord of the arc. This is the result when 4 segments are selected. For example. The Curve command is used to sub-divide a member into a number of segments that are chords of an arc. The single member forming the top chord is selected for the Curve command.
The prompts in the status bar guide you through the necessary steps in this command: • • • • Select nodes Select point as fixed point Select point as start point of stretch vector Select point as end point of stretch vector Coordinates of any point may be typed instead of clicking it with the mouse. you can abort the command by pressing the Esc key. The Structure > Move > Stretch command applies a linear transformation to the coordinates of selected nodes. In this example a member is added to represent it. All the nodes to be transformed are highlighted. The diagram below shows the truss on completion of the command. The stretch vector may be defined by selecting two points with the mouse or entering their coordinates. where the top chord nodes of a truss are "stretched" to introduce a uniform slope from one end to the other. If you inadvertently click on the wrong node when selecting the fixed node or the start of the stretch vector. Node 2 is selected as the fixed node. Microstran V9 6:Graphics Input • 127 .The Stretch Command If you complete a stretch command that does not have the desired effect you may . Nodes 12 and 14 are selected to define the stretch vector. An example is illustrated below. click the Undo button.
(equivalent to the View > Zoom > Extents/Limits command) will zoom the view so that the full structure and the limited part alternately fill the screen. . To hide the rest of the structure right-click and uncheck Show Outside Limits. LIMIT > WINDOW When the Limit command is in effect. clicking this button. The Limit > Window command. This has the advantage that the view you are working on is uncluttered by irrelevant detail and the rest of the structure is inaccessible while Limit is in effect.The Limit Command VIEW > LIMIT > WINDOW The commands on the View > Limit menu allow you to restrict activity to a selected part of the structure. was used to select one floor of the building structure in the diagram below. 128 • 6:Graphics Input Microstran V9 . . The rest of the structure may be greyed out or hidden from view.
was used to select another part of the same building structure in the diagram below. command. DEFINING THE BOUNDARY Clicking the Full View button. LIMIT > BOUNDARY The selection was made from a plan view by clicking a polygon enclosing the desired part of the structure. . . reverses the effect of the Limit Microstran V9 6:Graphics Input • 129 .The Limit > Boundary command.
The current job. After initiating the command you must select an archive files for each component model and a name for the new model. is closed and the new structure is opened in Microstran.Merging Two Models The Structure > Merge Models command creates a new structural model from two existing models. It shows the statistics of each component model and allows you to specify increments for node. Any overlap will result in entities with duplicate numbers and the merging of the models will fail. MERGE MODELS DIALOG BOX 130 • 6:Graphics Input Microstran V9 . The dialog box below is then displayed. if it exists. member. and load case numbers so that overlaps in these numbers may be avoided.
You can change the title of an existing load case by selecting it in the list box. Click the button with the red "stop sign" to exit from load input mode. Other load input commands are available on the Loads menu (see "Loads Menu Commands" on page 43). On clicking the New Load Case button or selecting the Loads > Add Case / Edit Title command the dialog box below is displayed. When you first add a load case you must determine whether it is a primary load case or a combination load case. ADDING A LOAD CASE Selecting the Input Load Case The Load Input toolbar contains a combo box with the name of the current input load case (see "Load Input Toolbar Commands" on page 55). one or more primary load cases and optionally. combination load cases (see "Load Case Titles (CASE)" on page 101). After entering load case details you may click the Add button to transfer the load case to the list box. Microstran V9 6:Graphics Input • 131 . You cannot input loads when this box is empty. Refer to Chapter 5 – "Structure & Load Data" for information on load types not covered below. Load Case Titles New Load Case The first step in entering load data is to define load cases. The input load case is selected in the combo box or with the Loads > Select Input Case command. The type of an existing load case cannot be changed but you can delete a load case and then add it again.Load Input Most load input tasks can be accomplished in Graphics Input with the buttons on the Load Input toolbar (see "Load Input Toolbar Commands" on page 55).
Member loads are entered in the Add Member Load dialog box. The force component corresponding to the vertical axis is initially selected. The load type is selected and the necessary load parameters are button provides pop-up help for each then entered. You may also right-click on a member and choose Input Member Loads from the context menu. Clicking the item in the dialog box. shown below. If more than one node is selected the specified load components are applied to all selected nodes. A blank box indicates that the selected nodes do not all have the same load component. NODE LOAD DIALOG BOX Member Loads Input Member Loads You may input member loads by clicking the Input Member Loads button or selecting the Loads > Member Loads command. Load components are entered in the Input Node Loads dialog box. shown below. You may also right-click on a node and choose Edit Node Loads from the context menu. MEMBER LOAD DIALOG BOX 132 • 6:Graphics Input Microstran V9 . The load entered will apply to all selected members. Any value entered will apply to all selected nodes.Node Loads Input Node Loads You may input node loads by clicking the Input Node Loads button or selecting the Loads > Node Loads command.
for a specified load case. You may select one of these and then edit or delete it. You can also add a new member load to all the selected members. Area Loading AreaLoading You may input floor loading by clicking on the Area Loading button or selecting the Loads > Area Loading command – see "Area Loading" on page 112.The Loads > Edit Member Loads command allows you to change loads that are common to a group of members. DIALOG BOX FOR EDITING MEMBER LOADS The Loads > Copy Member Loads command allows you copy the loads on a single member.e. to multiple target members. Combination components are entered in the Input Combinations dialog box. This command is also available on the member context menu. Combinations Load Cases Input Combination Case You may input combination load case components by clicking on the Input Combination Case button or selecting the Loads > Case Combinations command. Microstran V9 6:Graphics Input • 133 . All member loads common to the selected members are displayed in the dialog box shown below. For each component load case you must enter a factor and then click the Add button. You cannot input combination components unless the selected load case is a combination load case (i. shown below. type "C").
COMBINATION INPUT DIALOG BOX 134 • 6:Graphics Input Microstran V9 .
can be input with SSI. The extent to which section and material properties may be input with SSI varies from one standard structure to another.7:Standard Structures Input General Standard Structures Input (SSI) allows you to input structure data for several common types of structure by specifying a small number of defining parameters. STANDARD STRUCTURES INPUT Even if SSI cannot generate exactly what is required it is often useful to start the data input with SSI and then add to it or modify it as required with other input methods. All the types of structure shown. and also geodesic domes. Microstran V9 7:Standard Structures Input • 135 .
Sections For some types of standard structure. which have z moment releases at each end.What SSI Does Job Title. SSI assigns arbitrary section properties. Materials In some cases SSI offers the choice of materials and otherwise assigns the properties of steel or concrete to all members. Editing Data Created by SSI Once you have exited from SSI. except for the web members of triangular trusses. you will have to enter data again. The desired sections can then be specified with another input method. SSI determines units. In other cases. The numbering scheme can readily be altered by using the Structure > Renumber commands. and sections. structure type. and sections are numbered to facilitate identification and selection of member groups. tonnes. Other input methods must be used to add load data before analysing the structure. SSI allows you to select sections from a section library. If you go back to SSI to make a change. kN. Member Releases SSI makes all members rigidly connected to one another. In some cases there are gaps in the numbering sequences to permit insertion of additional nodes. Material properties can be changed as required with another input method. Use another input method to enter any additional member releases that are required. Plane frames have the Y axis vertical. 136 • 7:Standard Structures Input Microstran V9 . Numbering Scheme Nodes. and degrees Celsius. Units and Type The title for the job may be entered by selecting the Structure > Title command. Applied Loads SSI does not permit the entry of loads. members. according to structure type. members. the structure data may be changed as required with any other input method. such as Graphics Input or Table Input. Units are meters. and the vertical axis and these should not be changed.
Grillage A rectangular or skew grillage in the global XY plane.Choosing the Structure Type CHOOSING THE STRUCTURE TYPE The available structure types are: • • • • • • Continuous beam Single span or multi-span continuous. Z axis vertical. 3-D frame A rectangular multi-storey space frame. including an elastic foundation. 7:Standard Structures Input • 137 • • • • • Microstran V9 . Z axis vertical. Single bay portal frame Single bay portal frame. Multi-bay bay portal frame Multi-bay portal frame. Triangular truss Triangular roof truss. This type of structure is often used for the design of floor slabs in multi-storey buildings. Mono-slope and saw-tooth frames may be input with appropriate choice of input parameters. The span and height of each bay may be different. 2-D frame A rectangular multi-storey plane frame. Several web patterns are available. You must choose one of the feasible panel configurations listed for the specified parameters. Beam on elastic foundation Continuous beam of varying section on elastic foundation. A range of support conditions is available. Parallel chord truss Parallel chord truss. Sub-frame A structure consisting of a continuous beam with columns above and below. Trussed rafter portal frame Trussed rafter single bay portal frame. with or without ridge.
or tetrahedron. At each node the support conditions may be specified as fixed. each span having the same section properties. The number of spans. Geodesic dome Any geodesic dome based on the icosahedron. or cantilever (i. octahedron. pinned. You must specify the frequency (the number of subdivisions of the basic polyhedron face) and the class (the type of sub-division).e. no support). The structure is a plane frame with the Y axis vertical.• Trestle An equi-angular braced trestle. • Beams Continuous Beam CONTINUOUS BEAM SSI generates a continuous beam with up to ten spans. CONTINUOUS BEAM 138 • 7:Standard Structures Input Microstran V9 . the default span length. and the material type are specified in the dialog box shown below. sliding. Bracing may be in a "K" pattern or an "X" pattern. The arbitrary section and material properties can be changed with other input methods.
The subgrade modulus of the foundation material is specified for each beam segment. Compression members are not used in order to eliminate the possibility that they may buckle when non-linear analysis is used. Where kN and m are used.The span lengths and support conditions may be varied as required. Material properties for concrete are assigned – these values can be changed with other input methods if necessary. If section properties are input as zero SSI calculates the values that correspond to the specified width and depth. the units for subgrade modulus are kN/m3 (i. After specifying the number of segments. and depth. If the geometric properties of the section are entered as zero Microstran will compute them automatically. A non-linear analysis is then required.e. CONTINUOUS BEAM – SPAN LENGTHS Beam on Elastic Foundation SSI generates a continuous beam with varying section properties on an elastic foundation. SSI calculates section properties for the rods so that the axial stiffness of each rod is equal to the product of the subgrade modulus and the foundation contact area for that rod. The rods must be specified as tension-only members if it is necessary to take possible lift-off into account. Units used for the subgrade modulus must be consistent with units used elsewhere in the job. The structure is a plane frame with the Y axis vertical. width. you must enter data for each segment. The foundation material is represented by vertical tension rods fixed at the upper end and connected at the lower end to the nodes in each beam segment. Microstran V9 7:Standard Structures Input • 139 . kPa/m). Each beam segment is sub-divided into a number of members of equal length (the default value is 10). The beam is input as a number of segments of specified length.
Subgrade Modulus The subgrade modulus varies over a very wide range depending on the soil type and footing geometry. there are no member releases in the chord members). which has limitations in analysing soil/structure interaction. However. another to all bottom chord members and another to all web members. One section number is assigned to all top chord members. Typical values range from 10000 to 150000 kN/m3 for granular soils and from 20000 to 100000 kN/m3 for cohesive soils. The structure is a plane frame with the Y axis 140 • 7:Standard Structures Input Microstran V9 . while web members are pinned at each end (i. Trusses Triangular Truss TRIANGULAR TRUSS SSI generates a symmetrical triangular truss with web members connected to the chords at equal intervals in a "W" pattern.BEAM ON ELASTIC FOUNDATION Limitations of the Winkler Foundation The SSI beam on elastic foundation is a Winkler foundation model.e.e. The number of panels in the bottom chord must be an odd number between 3 and 19. if the spring stiffness values can be determined by reference to a known or estimated deflection pattern. they have a z moment release at each end). The chords are continuous (i. reasonable results may be obtained.
vertical. The arbitrary section and material properties can be changed with other input methods. The truss will be sloped if a value is entered for the rise between supports. The dialog box below is used to enter the parameters defining several types of parallel chord truss. the "vertical" web members are at right angles to the chords). a "W" pattern with verticals. PARALLEL CHORD TRUSS Microstran V9 7:Standard Structures Input • 141 . or an "N" pattern. the latter two patterns will produce crossed diagonals in the centre panel. If an odd number of panels is specified. The structure is a plane frame with the Y axis vertical. TRIANGULAR TRUSS Parallel Chord Trusses PARALLEL CHORD TRUSS SSI generates the data for parallel chord trusses with web members arranged in one of three possible patterns. In a sloped truss. The dialog box below is used to enter the parameters defining the triangular truss. The arbitrary section and material properties can be changed with other input methods. a "W" pattern.
Each bay of the portal frame is described by a wizard. Each bay of the portal frame may have a ridge located anywhere between the columns. The structure is a plane frame with the Y axis vertical. Sections are selected from the current steel library. each page of which is shown below.Typical parallel chord trusses are shown in the diagram below. TYPES OF PARALLEL CHORD TRUSS Portal Frames Single Bay & Multi-bay Portal Frames MULTI-BAY PORTAL FRAME SSI generates a wide range of single bay and multi-bay portal frames with a minimum of input effort. 142 • 7:Standard Structures Input Microstran V9 . and rafters may have a haunch at column connections.
3. delete the centre column with Graphics Input.PORTAL FRAME WIZARD Haunches Haunches are fabricated by welding a tee cut from an I section to the rafter at the column connection. it is not necessary to specify more than one or two segments to obtain accurate results. calculating the section properties at the centre of each segment. Microstran V9 7:Standard Structures Input • 143 . In most cases. Input the bay with the apex haunch as two bays each without an apex. A haunch is specified by the name of the section from which the tee is cut and the overall depth of the section at the face of the column (measured vertically). After exiting from SSI. 2. Specify the desired haunch on the right of the left-hand bay and on the left of the right-hand bay. Although SSI does not allow the input of a haunch at an apex. it is simple to achieve by the following procedure: 1. Microstran treats the haunch section as a number of prismatic segments.
The arbitrary section and material properties can be changed with other input methods. 144 • 7:Standard Structures Input Microstran V9 .e. The chords are continuous (i. SSI allows the entry of an estimate for the column width so that the truss geometry can be calculated for the length of the truss being taken as the distance between the column faces.e. All arrangements regarded as feasible are shown in the list box. they have a z moment release at each end). TRUSSED RAFTER PORTAL FRAME – CHOOSING ARRANGEMENT The above dialog box is used to enter the parameters defining the structure.Trussed Rafter Portal Frame SSI generates data for a single bay symmetrical portal frame with rafters formed by a truss with parallel chords. If zero is entered for the column width. A "dummy panel" is included between the face of the column and the centre-line of the column. TRUSSED RAFTER PORTAL FRAME SSI lists a number of feasible panel layouts from which you may choose the most suitable. The arrangement number is the number of panels along the top chord of one side of the truss (not counting the dummy panel that occurs when a non-zero column width is entered). there are no member releases in the chord members). while web members are pinned at each end (i. the length of the truss is taken as the centre-to-centre distance between the columns. The structure is a plane frame with the Y axis vertical. If a "+" is shown next to this number it means that there is an additional part panel on each side of the truss adjacent to the apex. This can be seen in the diagram below.
Columns are fully restrained at the levels above and below the beam. The structure is a plane frame with the Y axis vertical.TRUSSED RAFTER PORTAL FRAME – NUMBER OF PANELS Sub-frame SUB-FRAME SSI generates data for a sub-frame composed of a continuous beam with up to 10 spans with optional columns above and below the level of the beam. Set column height to zero to remove a column – a cantilever will have zero column lengths at the free end. from left to right. The arbitrary section and material properties can be changed with other input methods. The parameters necessary to specify the sub-frame are the span lengths and the lower and upper column heights. Microstran V9 7:Standard Structures Input • 145 .
referred to as the skew direction. The grillage is specified by the number of panels in each direction. One axis of the grillage is in the global X direction and the other. as shown in the diagram below. When elastic support is selected the subgrade modulus must be entered and the stiffness of each spring support is computed as the product of the subgrade modulus and the contact area for that spring. and the length of each panel. is rotated clockwise (in plan) from the Y axis direction by the skew angle.Grillage GRILLAGE SSI generates data for a grillage in the XY plane with Z vertical. The lengths of the skew panels are measured in the skew direction. 146 • 7:Standard Structures Input Microstran V9 . GRILLAGE . a skew angle.DIMENSIONS Supports Several alternative arrangements are available for the supports.
SUPPORTS 2-D Frame 2-D FRAME SSI generates data for a rectangular frame in the XY plane. Microstran V9 7:Standard Structures Input • 147 . The arbitrary section properties and concrete material properties can be changed with other input methods. The structure is a plane frame with the Y axis vertical. The input parameters are bay lengths in the X direction. storey heights and support conditions (pinned or fixed).GRILLAGE .
The arbitrary section properties and concrete material properties can be changed with other input methods. Trestle TRESTLE 148 • 7:Standard Structures Input Microstran V9 . The structure is a space frame with the Z axis vertical. Master-slave constraints are often used to model the rigid in-plane behaviour of concrete floor slabs in this type of structure and may be added if the master-slave option is available (see "Master-Slave Constraints" on page 96).3-D Frame 3-D FRAME SSI generates data for a three dimensional rectangular frame. The input parameters are bay lengths in the X and Y directions. storey heights and support conditions (pinned or fixed).
If a constant panel height is required. The arbitrary section properties and steel material properties can be changed with other input methods. The base nodes are pin supports. Supports. sections. and materials are not generated – these must be entered with another input method. The members in each polyhedral face have a different section number but they can easily be changed with another input method.SSI generates data for an equi-angular braced trestle with "K" or "X" pattern bracing. TRESTLE – DIMENSIONS Geodesic Dome GEODESIC DOME SSI generates data for geodesic domes based on the icosahedron. the octahedron. all panels are geometrically similar for structural efficiency and detailing convenience. The structure is a plane frame with the Y axis vertical. The dialog box below is used to enter the parameters defining the structure. Microstran V9 7:Standard Structures Input • 149 . In this type of structure. The parameters required to define the trestle are shown in the diagram below. The structure is a space frame with either the Y or Z axis vertical. or the tetrahedron. the trestle may be input in SSI without taper and then tapered with the Structure > Move > Stretch command.
The Z diameter is determined by Aspect ratio. Vertical axis When Z. a full sphere (or spheroid) will be generated. For Class 1.GEODESIC DOME – PARAMETERS • Diameter The X and Y diameters of the geodesic surface. triangles are rotated at right angles. subdivision triangles are aligned with the edges of the polyhedral faces. when Y. For a spherical surface this value is 1. • • • • • • 150 • 7:Standard Structures Input Microstran V9 . Frequency The order of the sub-division of each polyhedral face. the plan shape will be elliptical if the aspect ratio is not 1. Aspect ratio The ratio of the Z diameter to the X and Y diameters. If the height is equal to or greater than the vertical diameter. Polyhedron type A geodesic surface is an approximation to a spherical surface created by the triangulation on the circumsphere of each face of a regular polyhedron. All members in the same polyhedral face have the same section number. for Class 2. Three regular polyhedrons are available – the icosahedron has 20 faces. Height The height of the dome. the octahedron has 8. the geodesic dome is always circular in plan. Class The type of sub-division of the polyhedral faces. Frequency 1 means that the polyhedral faces are not sub-divided. and the tetrahedron has 4.
and review all job data in numerical form.8:Table Input General Table Input allows you to enter. for generating a series of new entities. TREE VIEW AND TABLE Double-click on any entity and a table is displayed in a dialog box. Microstran shows an icon next to each entity to provide a visual cue to the entity type – for example. This displays a tree view of the job data. A heading is shown for each type of entity and if there is a plus sign in a box. The dialog box has buttons for inserting and deleting rows. you may either click on it or double-click the entity header to expand the list of all such entities. An example is shown in the diagram. Microstran V9 8:Table Input • 151 . similar to that in Windows Explorer. modify. and in some cases. The diagram above shows the node table as it appears after double-clicking on node 2 in the tree view. It is initiated by clicking a button on the main toolbar or selecting the Table Input command on either the Structure menu or the Load menu. the icon next to each node shows whether the node is restrained.
SELECTED CELL When there is a caret in a cell. the resulting state of the cell depends upon the exact location in the cell where you clicked. Note: Deleting or renumbering an item in Table Input will invalidate other data that refers to it. EDITING CELL CONTENTS When you click on a cell with the mouse. 152 • 8:Table Input Microstran V9 . If you click away from the text in a cell (i. Double-clicking an item without children will display the corresponding table. How To Use Tables Selecting Cells Tables behave in a similar way to a spreadsheet. If you click on the text in the cell the caret will appear where you clicked and the cell will be ready for editing. any member that referred to the old node number will now refer to a nonexistent node and. When a cell is selected it is highlighted as shown in the diagram below.e. as shown below. the cell is ready for editing – anything you type will be inserted at the caret. Anything you type will completely replace the contents of the cell.. Double-clicking any item in the tree that has children (as shown by the plus sign in the box) will simply expand or contract the list of children. You can use Table Input either for editing an existing job or for making a new job. In all tables you can move around using the arrow keys on the keyboard or by clicking a cell with the mouse. Data may be entered in any convenient order because comprehensive consistency checks are not carried out until you close Table Input. to the left of a number). if you renumber a node. For example. the cell will be selected. unless you adjust the affected data in the member table.Note that context help (the question-mark button) can provide information on any item in the dialog box. Load and design data may also be invalidated by changes to structure data. the member will be lost when you save your changes.
Sorting rows in load tables quickly shows the loads with the greatest magnitude. The diagram below shows part of a table with a rectangular range selected. These are: Ctrl+X Ctrl+C Ctrl+V Ctrl+Z Cut (copy to clipboard and delete) Copy to clipboard Paste from clipboard Undo the last action Sorting Rows Double-clicking on any column header sorts the rows of the table according to the values in the selected column. The first time you double-click. 8:Table Input • 153 Microstran V9 . however. The number of the new entity is usually determined so that gaps in the numbering sequence are preserved. SELECTED RANGE Shortcut Keys There are several useful shortcut keys. the rows will be sorted into ascending order.You may select multiple cells by dragging the cursor over them (this is useful for deleting a number of rows or copying a range of cells). If only one cell is selected. If there is no gap in the entity number. no row will be inserted. if there is not a sufficient gap to the next entity the increment will be 1. The number of the new entity is usually determined so that gaps in the numbering sequence are preserved. however. If there is no gap in the entity number. The top left cell in the selected range has the focus. Insert Before Click this button to insert a new row before the current row (the row containing the cell with the focus). it has the focus. no row will be inserted. Double-click again and the rows will be sorted in the reverse order. Insert After Click this button to insert a new row after the current row. if there is not a sufficient gap to the next entity the increment will be 1.
so you can quickly delete a number of rows by clicking the Delete button repeatedly. On clicking OK in the dialog box. If you delete the last row in a table. Click the Update button to force an update of all items and at the same time. In other edit boxes. Table Input displays a warning to this effect when you save a job containing design data. A beep sounds to warn you when this occurs. No rows will be deleted if you click the No button. Also. Important Note: Design data cannot be input or modified using Table Input.Generate This button is not available for all entity types. clicking the Delete button will remove the row containing the selected cell. MULTIPLE DELETION WARNING When you delete a row the focus moves to the next row after the deleted row. In this way. validate them. If a range of cells is selected. in the node generation dialog box. clicking the Generate button displays a dialog box so you can specify a generation sequence. the newly generated entities are inserted into the table. 154 • 8:Table Input Microstran V9 . you can check the results of any change before clicking OK. Delete Row Where a single cell is selected. Where it is available. the focus moves up to the row before the deleted row. automatic update occurs only when the focus leaves the edit box. Multiple deletions are always preceded by a warning message such as that shown below. clicking the Delete button will remove all rows with one or more selected cells. other edit boxes change automatically. For example. when you change a "To" coordinate the corresponding increment changes. changes to structure or load data may invalidate existing design data. Invalid data items will be cleared and empty data items will be set to default values. As you enter data in some of the edit boxes in a generation dialog box.
NODES TABLE Microstran V9 8:Table Input • 155 . are omitted. You may input or modify all of these entitiy types using Table Input. Those shown bold are documented in detail in this section and the others. • • • • • • • • • • • Nodes Fixed supports Spring supports Node masses Master-slave constraints Members Member types Rigid member offsets Semi-rigid connections Sections Materials Nodes The dialog box below contains the table of node coordinates.Structure Entities Below is a list of all the types of structure data that may exist in a Microstran job. which behave similarly.
When you select a "From" or "To" node number that exists in the table. NODE OVERWRITE WARNING 156 • 8:Table Input Microstran V9 . A message is displayed to warn you of any overwriting of coordinates so you can decide whether to proceed or not. Any existing node whose number matches a node number in the generated series will be replaced by the generated node. New nodes are generated by interpolating between the "From" and "To" nodes. NODE GENERATION The initial "From" node is the node that was selected in the table.The Generate button displays the dialog box below. the coordinates in this dialog box will be updated automatically to those in the table.
You may type values directly into any cell in the 8:Table Input • 157 Microstran V9 .. buttons are provided to assist in the entry or display of an item in the respective columns. The Ref. Rel. and Dir.Fixed Supports FIXED SUPPORTS TABLE Clicking the Edit button provides a convenient way to inspect or change the restraint code. EDITING RESTRAINT CODE Members MEMBERS TABLE This dialog box contains the table of members..
EDITING REFERENCE NODE/AXIS The Rel. that are symmetrical about both axes. button displays a dialog box. button displays the dialog box shown below for the member section orientation code. such as I sections. which allows you to inspect or change the selected member releases. EDITING MEMBER RELEASES The Dir. The Ref.table but clicking one of these buttons displays the corresponding item of the current row in a dialog box. EDITING MEMBER SECTION ORIENTATION 158 • 8:Table Input Microstran V9 . Note that this item is not relevant for sections. button displays the member reference node/axis dialog box shown below.
New members are generated between the "From" and "To" members. Any existing member whose number matches a member number in the generated series will be replaced by the generated member.The Generate button displays the dialog box shown below. When you select a "From" member number that exists in the table. MEMBER GENERATION The initial "From" member is the member that was selected in the table. A message is displayed to warn you of any overwriting of members so you can decide whether to proceed or not. MEMBER OVERWRITE WARNING Microstran V9 8:Table Input • 159 . the member values in this dialog box will be updated automatically to those in the table.
The easiest way to enter a section property is to click one of the Library. The valid table entries depend on the Source field (LIBR. as shown below. The rightmost 6 columns of the table contain either geometric property values or shape dimensions. or PRIS).Member Types MEMBER TYPES TABLE To change the member type you may select from the available member types in the drop-down list box or type the code for the necessary member type as TONLY. CABLE. SHAP. Section Properties SECTION PROPERTIES TABLE The table for section properties is shown above. appropriate to the properties to be input. CONLY. 160 • 8:Table Input Microstran V9 . MGAP. Clicking these buttons displays a dialog box. or Values buttons. BFUSE. Shape. or PFUSE.
SECTION FROM LIBRARY SHAPE INPUT NUMERICAL VALUES Microstran V9 8:Table Input • 161 .
The dialog box containing the load case title table is shown below. For example. Double-clicking an item without children will display a table so you may enter entities of the selected type. Double-clicking any item in the tree that has children (as shown by the plus sign in the box) will simply expand or contract the list of children. When there are no primary load cases.You may paste values from the Windows clipboard into the table. if you displayed the dialog box from "Combination Load Cases" you cannot enter data for primary load cases. double-clicking on "Primary Load Cases" will display the dialog box for entering load case titles. Similarly. Existing load cases may be expanded to show all load data. Display titles of combination load cases similarly. 162 • 8:Table Input Microstran V9 . Load case numbers and load case types cannot be changed. LOAD CASE TITLES TABLE If you displayed this dialog box from "Primary Load Cases" you may not enter data for combination load cases. Only limited validation is performed in this table but more extensive checks are performed when you finally exit Table Input. you can copy a range of values from a spreadsheet with Ctrl+C and paste the range directly into the table at the appropriate location with Ctrl+V. If primary load cases exist you may display their titles by right-clicking on "Primary Load Cases" and selecting the Show Load Case Titles command on the context menu. Deleting a row in this table deletes the corresponding load case. Load Case Input The tree view shows "Primary Load Cases" and "Combination Load Cases" as top-level headings.
The Generate button displays the dialog box shown below.Load Types Below is a list of all the load types that may be input with Table Input. Those shown bold are documented in detail. • • • • • • • GRAV load Node loads Node temperatures Prescribed displacements Member loads Member temperatures Case combinations Node Loads NODE LOADS TABLE This dialog box contains the table of node loads for the selected load case. NODE LOAD GENERATION Microstran V9 8:Table Input • 163 .
the load values will be updated automatically to those in the table. When you select a "From" or "To" node number that exists in the table. A message is displayed to warn you of any overwriting of node loads so you can decide whether to proceed. Any existing load at a node whose number matches a node number in the generated series will be replaced by the generated node load. 164 • 8:Table Input Microstran V9 . The Edit button displays the dialog box shown below so you may conveniently inspect or change the selected member load. New node loads are generated by interpolating between the respective load components at the "From" and "To" nodes.The initial "From" node is the node that was selected in the table. NODE LOAD OVERWRITE WARNING Member Loads MEMBER LOADS TABLE This dialog box contains the table of member loads for the selected load case.
MEMBER LOAD OVERWRITE WARNING Microstran V9 8:Table Input • 165 . the corresponding load values will be updated automatically to those for the first load on that member in the table. Each generated member load is added to the selected load case.The Generate button displays the dialog box shown below. MEMBER LOAD GENERATION The initial "From" member is the member that was selected in the table. Existing member loads are not affected by generation. When you select a "From" member number that exists in the table. A message is displayed to warn you when you are about to add loads to members that already have one or more member loads. so you can decide whether to proceed. New member loads are generated between the "From" and "To" members. Load parameters are interpolated between the values for the "From" and "To" members. whether or not there are existing loads on the member.
166 • 8:Table Input Microstran V9 .
The archive file comprises these blocks: 1. displacing the current job. does make it useful in some situations. or 1.234E3). It is a convenient format for storage and transmission of job data. The Design Block (optional) contains data required for design of steel or reinforced concrete members. The Structure Block contains node. The archive file is also used by third-party programs to interface to Microstran. The statements and groups of statements in each block are described in this chapter.9:Archive File Input The archive file is a text file that describes the structure. or exponential format (e. 1234 or 1234. 4. An archive file is created for an existing job with the File > Export command. section. The Load Block (optional) describes the applied loading. It can be edited by selecting the File > Edit File command and it can be read into Microstran. The Parameter Block contains title information and specifies the type of structure. and design data. 5. Syntax The following rules apply to archive files: • • Items must be separated by one or more blank spaces (not commas). Archive File Input is not a primary input method. 3.g. member. 2. decimal. Microstran V9 9:Archive File Input • 167 . with the File > Import command. loading. and material data for the structure. The Set Block (optional) contains information about any specified sets. Numbers used for real values may be entered in integer. but the expanded format. where every entity in the structure is explicitly defined. You may refer to the sample archive files distributed with Microstran (one is listed in this chapter) to assist in interpreting the information that follows.
Parameter Block
Title Statements
* title1 * title2
title1 title2 First line of title (up to 60 characters of text). Second line of title (up to 60 characters of text).
Designer's Notes Group
* note
note Line of descriptive information for the job (up to 60 characters of text).
As many lines as required, each with an asterisk in the first column and a blank in the second.
Units Statement
UNIT nu ul uf um ut fl ff fm ft
nu ul uf um ut fl ff fm ft Unit set number. Valid unit set numbers are 1 through 6 as shown in the table below. Name of length unit. Name of force unit. Name of mass unit. Name of temperature unit. Conversion factor – number of length units in 1 meter. Conversion factor – number of force units in 1 kilonewton. Conversion factor – number of mass units in 1 tonne. Conversion factor – number of temperature units in 1°C.
The unit names ul, uf, um, and ut and the conversion factors fl, ff, fm, and ft are required only for user-defined units, i.e. when the unit set number nu is 6. If the UNIT statement is omitted, units of meters, kilonewtons, tonnes, and °C will be assumed. For more information, see "Units" on page 80.
Structure Type Statement
TYPE nt Structure type. Valid types are 1 through 5.
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For more information, see "Structure Type" on page 81.
Vertical Axis Statement
VERT nv Number of the global axis which is vertical in plotted views (1=X, 2=Y, 3=Z). The vertical axis may be determined by the structure type.
Structure Block
Node Coordinates Group
NODE n x y z r
n xyz r Node number. Coordinate values. Restraint code (e.g. 111110).
For more information, see "Node Coordinates" on page 82 and "Fixed Supports (Node Restraints)" on page 87.
Spring Supports Group
SPRN ns kx ky kz kmx kmy kmz
ns kx ky .. Node number where spring exists. Spring constants.
A spring is defined for each DOF at the nominated node for which a non-zero spring constant is specified. For more information, see "Spring Supports" on page 88.
Master-Slave Constraints Group
SLAV n n1 n2 n3 n4 n5 n6
n n1 n2 .. Node number. Number of master node for the particular DOF of the listed node – zero if no master node.
For more information, see "Master-Slave Constraints" on page 96. This data group is applicable only when the Master-Slave Constraints option is available.
Microstran V9
9:Archive File Input • 169
Member Group
MEMB m na nb nc ns nm mra mrb dir
m na nb nc ns nm mra mrb dir Member number. End "A" node number. End "B" node number. Reference node/axis. Section number. Material number. End "A" release code. End "B" release code. Cross-section direction code.
For more information, see "Member Definition" on page 83.
Member Type Group
MTYP m mt Lo/Gcomp Gtens
m mt Lo/Gcomp Member number. Member type – TONLY, CONLY, CABLE, MGAP, BFUSE, or PFUSE. Unstrained length for cables only (if zero, chord length will be used), compression gap for gap member, maximum compression force for fuse member. Tension gap for gap member, maximum tension force for fuse member.
Do not include ordinary members. For more information, see "TensionOnly & Compression-Only Members" on page 97, "Cable Members" on page 98, and "Gap & Fuse Members" on page 99.
Member Modification Group
MOFF m axes xa ya za xb yb zb
m axes xa ya .. xb yb .. Member number. Axes in which the offsets are specified – GL for global, LO for local. Offset from node "A" to end "A" of member. Offset from node "B" to end "B" of member.
The MOFF line allows specification of rigid offsets at the ends of members. For more information, see "Rigid Member Offsets" on page 94.
170 • 9:Archive File Input Microstran V9
MSPR m kxa krya krza kxb kryb krzb
m kxa krya krza kxb kryb krzb Member number. Axial stiffness along member x axis of spring at end "A". Stiffness about member y axis of spring at end "A". Stiffness about member z axis of spring at end "A". Axial stiffness along member x axis of spring at end "B". Stiffness about member y axis of spring at end "B". Stiffness about member z axis of spring at end "B".
The MSPR line allows specification of semi-rigid connections between the rigid offset and the elastic portion of the member. For more information, "Semi-Rigid Connections" on page 95.
Sections Properties Group
This data group is used to specify the geometric properties with respect to the principal axes of the member cross-sections. For more information, see "Section Properties" on page 88. The section properties for each section number may be defined by one of the input methods below:
Selection from Library
PROP np LIBR lib_name sect_name ax ay az j iy iz Keyword. Name of library – up to 10 characters. Name of section – up to 15 characters. Cross-section axis (either X or Y) that is coincident with the member y axis. Comment – up to 20 characters. Section geometric property values. axis comment
LIBR lib_name sect_name axis comment ax ay ..
Note: When the nominated library file is available, Microstran takes section property and section outline data directly from the library, ignoring the values on the second line of the PROP record. If the library is not available, however, the geometric property values are used. In this case, the associated members cannot be rendered, nor checked to a steel design code.
Microstran V9
9:Archive File Input • 171
Shape Input
PROP np SHAP shape_code sect_name d1 d2... Section number. Keyword. RECT, CIRC, TUBE, LLT, LRT, LLB, LRB, TT, TB, I, or BOX. Name of section – up to 15 characters. Comment – up to 20 characters. The dimensions necessary to define the shape. These are listed below for each shape. comment
np SHAP shape_code sect_name comment d1 d2 ..
RECT d1 d2 d3 d4 d5 d6
1 2
L1 D Tw Bf Tf -
T2 D Tw Bf Tf -
I D Tw Btf Ttf Bbf Tbf
BOX D Tw Bf Ttf Tbf -
Applies to LLT, LRT, LLB, and LRB sections. Applies to TT and TB sections.
Property Value Input
PROP np PRIS sect_name comment ax ay az j iy iz Section number. Keyword. Name of section – up to 15 characters. Comment – up to 20 characters. Section geometric property values.
np PRIS sect_name comment ax ay ..
172 • 9:Archive File Input
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Materials Group
MATL nm e pr dens alpha
nm e pr dens alpha Material number. Young's modulus. Poisson's ratio. Mass density. Coefficient of thermal expansion.
This data group is used to specify material properties. For more information, see "Material Properties" on page 92.
Node Mass Group
NMAS n m Node number. Mass.
n m
For more information, see "Node Mass" on page 93.
Load Block
Each load case commences with a CASE statement and is terminated by either the CASE statement for the next load case, or an END statement.
Case Statement
CASE lcn desc Load case number. Description or load case title, up to 50 characters.
lcn desc
Several different load types may be included in each load case. These are set out below.
Acceleration Group
GRAV gx gy gz
gx gy gz Acceleration in global X direction. Acceleration in global Y direction. Acceleration in global Z direction.
For more information, see "Acceleration Loads (GRAV)" on page 102.
Microstran V9 9:Archive File Input • 173
Node Loads Group
NDLD n fx fy fz mx my mz
n fx fy .. mx my .. Node number. Node force values. Node moment values.
For more information, see "Node Loads (NDLD)" on page 102.
Member Loads Group
MBLD m form type axis scale f1 x1 f2 x2
MBLD m DIST type scale f1 x1
m form type axis scale f1 x1 f2 x2 Member number. CONC, UNIF, TRAP, TRI1, TRI2. FX, FY, FZ, MX, MY or MZ. GL or LO. LE or FR. May be omitted for UNIF and TRI1 loads. Magnitude at start of load. Distance from end "A" to start of load. Magnitude at end of load. Distance from end "A" to end of load.
Load forms are fully described in "Member Loads (MBLD)" on page 103. The number of parameters required depends on the load form (e.g. UNIF loads require f1 only). Member distortions are defined as member loads with the load form keyword DIST and the parameters axis, f2, and x2 omitted.
Node Temperatures Group
TEMP n t Node number. Node temperature differential.
n t
For more information, see "Node Temperatures (TEMP)" on page 109.
Member Temperatures Group
MBLD m MTMP tx ty tz
174 • 9:Archive File Input
Member number.
Microstran V9
For more information. even if there are no other statements in the load block. Factor by which load case is multiplied before adding to combination load case. Microstran V9 9:Archive File Input • 175 . Prescribed Displacements Group NDIS n dx dy dz rx ry rz where: n dx dy . Effective thermal gradient in member z direction. Prescribed rotation components (radians). It must be present. see "Prescribed Node Displacements (NDIS)" on page 111. END Statement END This statement terminates the load block.. rx ry . Prescribed displacement components. Effective thermal gradient in member y direction. For more information. Combination Load Case Group COMB lcn f Load case number for a previously defined load case. see "Combination Load Cases (COMB)" on page 114. where: lcn f Load cases containing combinations must not contain any other load. For more information. see "Member Loads (MBLD)" on page 103.. Node number.tx ty tz Centroidal temperature differential.
Design Data Statement $ design data This statement marks the beginning of the design data. Any legitimate combination of these codes: N = no restraint. Effective length factor for XX column buckling. OFFS off TF tfc BF bfc LH lh KX kx KY ky where: m1 m2 . "UB".. Section type mnemonic. Steel grade... L = effective lateral restraint. R = rotational restraint (in plan). It exists in archive files exported by Microstran only when one or more members have been initialized for steel or reinforced concrete design. Maximum depth of section. bfc lh kx ky There is one SMEM statement for each member for which there is steel design data.. Maximum slenderness ratio.. B = bottom flange. e.Design Block This block of the archive file stores information needed for Microstran's steel design and reinforced concrete design modules.. C = continuous restraint.. CODE code DSEC sec GR gr MAXSL sl & DMAX dmax & OFFS off TF tfc BF bfc LH lh KX kx KY ky . Offset from "A" end of member. The "&" character indicates the continuation of the SMEM. Design code. Keywords are shown in upper case and design parameters in lower case.. L = effective lateral restraint. code sec gr sl dmax off tfc Member numbers of all members in linked design member. 176 • 9:Archive File Input Microstran V9 ... S = shear centre. Bottom flange restraint codes. Effective length factor for YY column buckling.g. E = elastic restraint. D = destabilizing. CBEM. and CCOL statements on the next line of the archive file. R = rotational restraint (in plan). Top flange restraint codes. E = elastic restraint. Steel Design Group SMEM m1 m2. Any legitimate combination of these codes: N = no restraint. C = continuous restraint. Load height code: T = top flange. ..
Clear cover to bottom reinforcement. Yield stress of main reinforcement. N = ignore torque. top. Minimum bar diameter. Maximum number of layers of reinforcement.. bottom.] CODE code FC fc FSY fsy FSYV fsyv & SHAPE shape D d BW bw [BF bf TF tf] & DMTOP dmtop DMBTM dmbtm DSHEAR dshear & NPLEG npleg MLTOP mltop MLBTM mlbtm & CTOP ctop CBTM cbtm TORQ torq where: m1 m2 . bottom. Y = design for torque. Minimum bar diameter. Section shape code. Minimum bar diameter. Number of pairs of legs in shear reinforcement. shear reinforcement. Section dimension. Microstran V9 9:Archive File Input • 177 .Reinforced Concrete Design Group CBEM m1 [m2. Section dimension.. Section dimension. Maximum number of layers of reinforcement. There is one CBEM statement for each RC member to be designed as a beam.. code fc fsy fsyv shape d bw bf tf dmtop dmbtm dshear npleg mltop mlbtm ctop cbtm torq Member numbers of all members in linked design member. Section dimension. Clear cover to top reinforcement. Yield stress of shear reinforcement. top. Characteristic strength of concrete. Design code.
Minimum bar diameter. END Statement END This statement terminates the design block. bars in face parallel to section XX axis. Clear cover to ties. Width of rectangular column (dimension parallel to section XX axis). For rectangular column. Section shape code (RECT or CIRC). main bars. CODE code FC fc FSY fsy SHAPE shape & {BX bx BY by NBX nbx NBY nby | DIA dia NB nb} & [SWAY xy] DBMIN dbmin DT dt COVER cvr QONG qong where: m1 m2 . or XY if not braced in specified section direction. no. Yield stress of main reinforcement.CCOL m1 m2. bars for circular column. Y.. no. Design code. Minimum bar diameter. No. Ratio Q/G for design. Sway code – X. 178 • 9:Archive File Input Microstran V9 .. code fc fsy shape bx by nbx nby dia nb xy dbmin dt cvr qong Member numbers of all members in linked design member. bars in face parallel to section YY axis. Depth of rectangular column (dimension parallel to section YY axis). ties. Diameter of circular column section. For rectangular column. There is one CCOL statement for each RC member to be designed as a column.. Characteristic strength of concrete.
a hyphen indicating a range of values. are not required when the list is empty.Set Block This block of the archive file stores information about any defined sets. A list of section numbers. A list of material numbers. List values are separated by commas or hyphens. where: memblist nodelist sectlist matlist The keywords "MEMBLIST" etc. END Statement END This statement terminates the archive file. Microstran V9 9:Archive File Input • 179 . SET name MEMBLIST NODELIST SECTLIST MATLIST memblist nodelist sectlist matlist A list of member numbers. A list of node numbers.
000 180 DMAX 9999.0000 0.000 KY 1.0000 24.0000 0.000 KY 1.000 OFFS L SMEM 4 CODE AS4100 OFFS 0.500 -2.0000 5.0000 24. 1.0000 1 1 1 1 111110 001110 001110 001110 111110 000000 000000 000000 000000 000000 000000 000000 000000 0.3 SET COLUMNS MEMBLIST 1. 1.8600E-04 Y 7.000 0.000 0.000 0.000 0.000E-01 7.500 1.3800E-05 5.4 END DSEC UB TF L TF L DSEC UB TF L TF L DSEC UB TF L TF L DSEC UB TF L TF L GR BF BF GR BF BF GR BF BF GR BF BF NORMAL MAXSL L LH S KX L LH S NORMAL MAXSL L LH S KX L LH S NORMAL MAXSL L LH S KX L LH S NORMAL MAXSL L LH S KX L LH S 180 DMAX 9999.0000 1 2 3 4 2 3 4 5 1 LIBR Asw 1.5600E-06 3.000 2 LIBR Asw 1.000 530UB92.000 0.6000E-02 0.0000 7.000 OFFS L SMEM 2 CODE AS4100 OFFS 0.4000 5.000 -50.000 0.000 610UB125 0.000 4 1.000 3 1.000 OFFS L SMEM 3 CODE AS4100 OFFS 0.0000 0.000 Y 1. 1.000 3 LATERAL LOAD 2 50. 1.000 2 CONCENTRATED LOAD AT APEX 3 0.000 $ design data SMEM 1 CODE AS4100 OFFS 0.0000 -X Y Y X 1 2 2 1 0.000E+08 3.850E+00 1.0000 0.080E-05 1 DEAD LOAD 2 UNIF FY 3 UNIF FY GL GL -4.4 0.000 180 DMAX 9999.0000 0. * PORTAL FRAME * * * VERS TYPE VERT UNIT NODE NODE NODE NODE NODE MEMB MEMB MEMB MEMB PROP PROP 5 3 2 1 m 1 2 3 4 5 1 2 3 4 kN T C 0.9300E-05 9.000 KY 1. This was produced from Example 2 in Chapter 20 (see "Example 2 – Portal Frame" on page 345).0000 0.0000 12.000 180 DMAX 9999.000 0.000 180 • 9:Archive File Input Microstran V9 .000 5 CASE 1 + CASE 4 1 1.000 6 CASE 2 + CASE 3 2 1.000 KY 1.000 4 WIND LOAD 1 UNIF FX 2 UNIF FY 3 UNIF FY 4 UNIF FX 0.000 0.Archive File Example An example of an archive file is listed below.000 GL LO LO GL 3.500 1.000 OFFS L END SET RAFTERS MEMBLIST 2.7500E-07 2.1800E-02 0.5400E-04 MATL CASE MBLD MBLD CASE NDLD CASE NDLD CASE MBLD MBLD MBLD MBLD CASE COMB COMB CASE COMB COMB END 1 2.000 -4.
Comments are shown in italics. 2 3 CONC FY GL LE -20.LIB 410UB53. to 5 20. $ 25 kN/m throughout. 0. . REFERENCE NODES ALL AXIS Y SUPPORTS ALL FIXED BUT FX MZ 1 PINNED MEMBER PROPERTIES ALL LIBR ASW. END Microstran V9 10:Macro Language Input • 181 . MLI EXAMPLE TITL1 4-Span Continuous Beam UNITS kN m t C TYPE PLANE FRAME VERT Y NODE COORDINATES 1 0. $ 20 kN at 1 m from start of member 2. 1.LIB STEEL CASE 1 Vertical loads MEMBER LOADS ALL UNIF FY GL -25.5 $ Central 10 kN load on first and last spans.7 $ Take section properties from library file. MATERIAL ALL LIBR MATL. MEMBER INCIDENCES 1 1 2 TO 4 $ Unit increments are assumed for member number $ and start and end node numbers. 1 4 CONC FY GL FR -10. 0. 0.10:Macro Language Input General The Macro Language Input file required to input the 4-span continuous beam shown is listed below. 0. $ Generate nodes at 5 m spacing.
3. • • • • • • 182 • 10:Macro Language Input Microstran V9 .Microstran's Macro Language (MLI) is a special language that allows you to describe a structure and the loads in familiar terms using keywords and labels to organize the data. The semi-colon (. perhaps only one or two changes may be necessary in the MLI file.234E3). decimal or exponential format (e. or WordPad. The Parameter Block contains title information and specifies the type of structure. The statements and groups of statements in each block are detailed in this chapter. An MLI data file comprises three blocks: 1. Upper and lower case may be used interchangeably. Where data consists of a set of labels and values (e. Numbers used for real values may be entered in integer. or spherical systems and many powerful generation facilities are provided. section property input) the labels may be omitted if the numeric values are entered strictly in the order shown. 2. MLI is an efficient means of inputting data. Statements may extend over two or more lines by terminating each incomplete line with a hyphen (-). If a dimension of such a structure is changed. The Structure Block contains geometry and property data for the structure. The MLI data file is a text file with file name extension "mli". such as MsEdit. Numbers used for repeat specifications etc. Notepad. must be integers. or 1. Any data following the $ character will be ignored by MLI. cylindrical. The Load Block describes the applied loading. Node coordinates may be given in rectangular. The "$" character is used to make a comment line or add a comment at the end of a line. Keywords and labels may be abbreviated to the first four characters. particularly for regular structures. The maximum line length is 80 characters. usually created and edited with a text editor. Syntax The following rules apply to MLI data files: • • Items must be separated by one or more blank spaces (not commas).g.) may be used to separate several statements of the same kind on a single line. 1234 or 1234.g.
n1 n2 . Square brackets indicate optional items (e.. [INC dn.g. Keyword defining a list that includes all elements. The dots do not appear in the MLI statement. • • • Lists MLI input makes extensive use of lists to generate data. Keyword.Notation The following notation is used in this manual: • Braces indicate that at least one of the enclosed items must be selected. The nodes ns and ne must have been previously defined and the increment ni must be consistent with the difference between start and end values.g. ns TO ne INC ni nj nk . End of generated sequence. Integer numbers..]] nj nk .. In this manual keywords and labels are shown in upper case while variables (used for text and numbers describing the structure) are shown in lower case. This convention is not required in MLI files – you may use upper and lower case interchangeably. or ALL or OTHERS where: n1 n2 . i. ns [TO ne [INC ni.. The brackets do not appear in the MLI statement. A list defines a set of numbers (e. Start of generated sequence.. A series of dots indicates that the preceding item(s) may be repeated one or more times.. Optional generation increment (defaults to 1). When the braces are shown on one line.g. Keyword. the range specified must be an exact multiple of the increment. node numbers) and lists may also contain the keywords TO and INC to generate part of the list. Keyword defining a list that includes all elements not already specified. vertical bars are used as separators (e. Any list may be extended over two or more lines by placing a hyphen at the end of each incomplete line.e. Neither the braces nor the vertical bars appear in the MLI statement.]). {A | B | C}). Microstran V9 10:Macro Language Input • 183 . ALL OTHERS Integer numbers.
mass. Values extracted from the section library and the material library will be transformed to the specified structure units. force.g. See "Structure Type" on page 81. The set of units chosen should be consistent (e. If the UNITS statement is omitted. Second line of title (up to 60 characters of text). The structure type and vertical axis are used to select the initial graphics view. tonnes. units of meters. For more information refer to "Units" on page 80.Examples: 1 2 5 7 11 12 17 7 TO 16 INC 3 1 2 5 7 TO 16 INC 3. and temperature to be used. 21 23 $ Discrete items $ Generated list $ Composite list Parameter Block Title Statements TITL1 title1 TITL2 title2 where: title1 title2 First line of title (up to 60 characters of text). Plane trusses and frames have the Y axis vertical while grids have the Z axis vertical. Space structures may be defined with any global axis vertical. 184 • 10:Macro Language Input Microstran V9 . tonnes). and °C will be assumed. meters. kilonewtons. Structure Type Statement TYPE PLANE {TRUSS | FRAME | GRID} or TYPE SPACE {TRUSS | FRAME} VERT {X | Y | Z} Plane structures always lie in the XY global plane. Units Statement UNITS {m } {mm} {ft} {in} {kN } {N } {kip} {t } {C} {F} {kg } {lbs} The UNITS statement defines the units of length. kilonewtons.
Coordinates of last generated node. the coordinates (x1. If no REPEAT ALL command has been given the repeat action is carried out from the beginning of the node coordinate input. Nodes are generated in the current coordinate system. ns xs ys zs TO ne xe ye ze INC dn Node numbers. REPEAT [ALL] nrep INC dn dx dy dz where: nrep INC dn dx dy dz Number of repeats. .Θ. Coordinate values specified on any statement refer to the current axis system. respectively. Coordinate values. Number of first generated node.. Any number of node coordinates may be defined on a single line by using a semi-colon (... Coordinate increments for each repeat. If ALL is omitted the repeat action is carried out only for the Microstran V9 10:Macro Language Input • 185 . Node number increment for each repeat.) as a separator. ns xs ys ys [TO ne xe ye ze [INC dn. Node number increment for generation. the node number increment. .]] where: n1 n2 .Z) or (R.z1) above will actually be (R.Structure Block Node Coordinates Group NODE COORDINATES n1 x1 y1 z1. which will be the global rectangular system unless the statement is preceded by an axis system statement or a secondary axis system statement (see below). Keyword to introduce last generated node.Φ) coordinates. If the keyword ALL is present the repeat action is carried out for all the nodes input since the last REPEAT ALL command. Keyword to introduce repeat increment values. The REPEAT statement may appear in the node coordinates group to copy previously entered coordinate data. x1 y1 . See "Node Coordinates" on page 82. Long lines may be broken into two or more lines by using a hyphen (-) at the end of each incomplete line. If a cylindrical or spherical axis system is in effect. n2 x2 y2 z2. Keyword to introduce node number increment. Number of last generated node. Uniformly spaced nodes may be generated by specifying the TO node and optionally. Coordinates of first generated node.y1. If the increment is not specified it is assumed to be 1.Θ..
and Z is the height. cylindrical. R is the radius. CYLINDRICAL (R.Θ. Keyword to denote the name of the primary axis which is parallel to the secondary X axis. At the completion of node coordinate input all coordinates are transformed to the primary rectangular axis system. Z coordinates may be omitted. Coordinates of the new origin. All coordinates following this declaration will be in the specified coordinate system. The coordinates of the nodes of the structure are given in two or three dimensional space.Y. Keyword to denote the name of the primary axis which is parallel to the secondary Z axis. You may change axis systems as many times as necessary.Z) Rectangular coordinates are the default coordinate system and will be used if no other system is declared. positive if the node is above the plane and negative if below it. measured in a right-handed sense from the X axis.Θ. 186 • 10:Macro Language Input Microstran V9 . For structures wholly within the XY plane. Rectangular. Θ is the rotation in degrees about the Z axis. Secondary Axis System Statement {RECTANGULAR} {CYLINDRICAL} {SPHERICAL } ORIGIN XC x YC y ZC z AXIS {X} {Y} {Z} ZERO {X} {Y} {Z} where: ORIGIN XC YC ZC xyz AXIS ZERO Keyword to introduce coordinates of origin of secondary axis system. SPHERICAL (R. R is the radius. and Φ (the latitude coordinate) is the angle measured from the XY plane. Labels for the origin coordinate values. Axis System Statement {RECTANGULAR | CYLINDRICAL | SPHERICAL} This statement may appear anywhere within the node coordinates group to define the coordinate system to be used for subsequent input. or spherical systems may be used. measured in a right-handed sense from the X axis.nodes input by the previous line in the MLI file (lines that have been extended with a hyphen at the end are regarded as a single line by the REPEAT function).Z) In cylindrical coordinates. RECTANGULAR (X.Φ) In spherical coordinates. Θ (the longitude coordinate) is the rotation in degrees about the Z axis.
Coordinate Transformation Group Translational and rotational transformations may be applied to node coordinates by using the TRANSLATE and ROTATE keywords in the node coordinates group. Y. and SPHERICAL keywords to specify a secondary axis system with an origin and axis orientations which may differ from those of the primary rectangular system. Rotation angles (degrees).10) in the primary system. the X. CYLINDRICAL AXIS X ZERO Y This statement defines a set of cylindrical axes with the same origin as the primary axes. Rotations are applied to the node coordinates in the order in which they are specified and do not need not be given in X. the secondary axes are parallel to the primary axes. In this case. Positive rotations cause the structure to move in a right-handed sense about the nominated axis of the primary rectangular axis system. This would be appropriate for the definition of the nodes of a tubular structure aligned with the primary X axis. All coordinates to be translated are transformed to the primary rectangular axis system before the translation is applied. CYLINDRICAL. Additional fields may be used with the RECTANGULAR. The transformation commands allow you to define node coordinates with the structure in the most convenient position and then re-position it as required. Examples: SPHER XC 10 YC 10 ZC 10 AXIS Z ZERO X This statement defines a set of spherical axes with origin at (10. Y and Z axes of the two sets of axes are parallel. ROTATE {ALL | list} RX rx RY ry RZ rz where: RX RY RZ rx ry rz Labels for rotation angles. The TRANSLATE statement causes the nodes of the complete structure or a part of it to be moved with respect to the global axes. Zero components of the translation do not need to be specified. 10:Macro Language Input • 187 Microstran V9 . Z order. The ROTATE statement causes the nodes of the complete structure or a part of it to be rotated about the global axes.10. If no AXIS or ZERO keyword is used. TRANSLATE {ALL | list} DX dx DY dy DZ dz where: DX DY DZ dx dy dz Labels for translation offset values. the cylindrical Z axis parallel to the primary X axis and the cylindrical X axis parallel to the primary Y axis. Zero rotation angles do not need to be specified.XYZ Axis names. Distances by which nodes are moved.
List of label/stiffness pairs. However. See "Master-Slave Constraints" on page 96.e. any set of pairs from KFX/kfx KFY/kfy KFZ/kfz KMX/kmx KMY/kmy KMZ/kmz.3E6 $ Support with rotational spring – 30 FIXED BUT KMZ 4. translational and rotational DOF fixed). rotational DOF not restrained). See "Fixed Supports (Node Restraints)" on page 87 and "Spring Supports" on page 88.Note that where multiple rotations are specified. Unconstrained DOF should be omitted. 188 • 10:Macro Language Input Microstran V9 . translational DOF restrained. Any individual degrees of freedom (DOF) may be released by listing them after the keyword BUT. For example. Labels identifying DOF for which master node follows. Keyword introducing constraint relationships.e. Number of master node for the particular DOF of the listed node. the final orientation depends on the order in which the rotations are specified. This data group is applicable only when Master-Slave Constraints is available.. KMX is a label introducing the rotational stiffness value kmx. List of nodes having the specified constraints. any set from the labels FX FY FZ MX MY MZ. Keyword which denotes listed nodes as pinned supports (i. Examples: $ Roller support – 10 FIXED BUT FX MZ $ Support with vertical spring – 20 FIXED BUT MZ KFY 2. Supports Group SUPPORTS list PINNED list FIXED [BUT release_list [spring_list]] where: list PINNED FIXED release_list spring_list List of nodes that are supports. FZ cannot be released in a plane frame.5E6 Master-Slave Constraints Group MASTER SLAVE list MAST DX n1 DY n2 DZ n3 RX n4 RY n5 RZ n6 where: list MAST DX DY .. These are slave nodes. Keyword which denotes listed nodes as fixed supports (i. those DOF suppressed because of the structure type cannot be released. List of actions to be released at support node. KFX is a label introducing the stiffness value kfx. n1 n2 .
Any number of member incidences may be defined on a single line by using a semi-colon (. nb1 nb2 .) as a separator.. End "A" node number increment for generation. See "Member Definition" on page 83. If the keyword ALL is present the repeat action is carried out for all the members given since the last REPEAT ALL command. Regularly numbered members may be generated by specifying the TO member and the (optional) member number and end node increments. m2 na2 nb2. End "B" node numbers. End "A" increment for each repeat.Member Incidences Group MEMBER INCIDENCES m1 na1 nb1. REPEAT [ALL] nrep INC dm dna dnb where: nrep INC dm dna dnb Number of repeats. End "B" increment for each repeat. End "B" node number of first generated member.. Number of last generated member. End "B" node number increment for generation. Number of first generated member. Any increments not specified are assumed to be 1. If no REPEAT ALL command has been given the repeat action is carried out from the beginning of the member incidence input. Member number increment for generation. ms nas nbs TO me INC dm dna dnb Member numbers End "A" node numbers. Keyword to introduce generation increment values.]] where: m1 m2 . . na1 na2 . Long lines may be broken into two or more lines by using a hyphen (-) at the end of each incomplete line. Keyword to introduce repeat increment values.. Member number increment for each repeat. The REPEAT statement may appear in the member group to copy previously entered member incidence data. If ALL is omitted the repeat action is carried out only for the members input by the previous line in the MLI file (lines that have been extended with a hyphen at the end are regarded as a single line by the REPEAT function). ms nas nbs [TO me [INC dm dna dnb. . Keyword to introduce last generated member number. Microstran V9 10:Macro Language Input • 189 ... End "A" node number of first generated member.
Keyword denotes listed members as cables. The position of the reference or "C" node (together with the member nodes "A" and "B") is used to define a plane that contains the member y 190 • 10:Macro Language Input Microstran V9 . Keyword denotes listed members as brittle fuse members. Keyword denotes listed members as compression-only. Keyword to introduce member type. Compression gap for gap members. Number of reference node "C" used to define member xy plane. compression force for fuse members. Keyword to introduce reference axis. Tension gap for gap members. Keyword which denotes listed members as tension-only. Name of global axis (any one of X Y Z -X -Y -Z) used to define the member xy plane.Member Types Group MEMBER TYPES list TYPE {TONLY | CONLY} or MEMBER TYPES list TYPE CABLE Lo or MEMBER TYPES list TYPE {MGAP | BFUSE | PFUSE} Gcomp Gtens where: list TYPE TONLY CONLY CABLE MGAP BFUSE PFUSE Lo Gcomp Gtens List of members which are of following type. Reference Node/Axis Group REFERENCE NODE list NODE n or REFERENCE NODE list AXIS axis where: list NODE n AXIS axis List of members. Keyword denotes listed members as plastic fuse members. Unstrained length of cable (0 = chord length). Keyword denotes listed members as gap members. max. tension force for fuse members. All these member types require non-linear analysis. max. Keyword to introduce number of reference node.
SEMI RIGID list SPRINGS KXA kxa KRYA krya KRZA krza KXB kxb KRYB kryb KRZB krzb Microstran V9 10:Macro Language Input • 191 .. XB YB . See "Member Definition" on page 83.axis. List of released actions – any labels from the set FX FY FZ MX MY MZ. List of members with specified modification... See "Member Definition" on page 83. Keyword to introduce releases at end "B" of member. Member Releases Group MEMBER RELEASES list ENDA lista ENDB listb where: list ENDA lista ENDB listb List of members with specified releases. The rules for determining which reference axis will be used by default are set out in Chapter 5 – "Structure & Load Data". Keywords introducing offset values. Keyword to introduce member offset data. Keyword to introduce releases at end "A" of member. The coordinates of the reference node must have been defined. Offset in global axis directions from node "B" to end "B" of member. The transverse member axes y and z are the principal axes of the member cross-section.. Any force may be released provided that the member remains stable and attached to the structure. Keywords to introduce offset values. A default reference axis will be chosen for any member that is not included on a reference node/axis list. The positive y axis lies on the same side of the member as the "C" node. Force or moment releases may be specified at the ends of members. If a reference axis is specified the member xy plane is parallel to the nominated global axis and the member y axis points towards that axis. xb yb . List of released actions – any labels from the set FX FY FZ MX MY MZ. Member Modification Group RIGID OFFSETS list OFFSET XA xa YA ya ZA za XB xb YB yb ZB zb where: list OFFSET XA YA . Offset in global axis directions from node "A" to end "A" of member. xa ya .
where: list SPRINGS KXA kxa KRYA krya KRZA krza KXB kxb KRYB kryb KRZB krzb List of members with specified modification. Properties must be defined for all members. Any omitted properties are set to zero. Stiffness value.. If the keywords AX AY etc. Keyword introducing stiffness in member x axis direction of spring at "A". This data group allows the specification of rigid offsets at the ends of members and semi-rigid connections between the rigid offset and the elastic portion of the member. Stiffness value. Member Properties Group MEMBER PROPERTIES list PRIS AX ax AY ay AZ az IX ix IY iy IZ iz or list LIBR lib_name sect_name where: list PRIS AX AY . See "Rigid Member Offsets" on page 94 and "Semi-Rigid Connections" on page 95. Keyword introducing stiffness in member x axis direction of spring at "B". Keyword. properties must be given in the specified order. Section geometric property values. Keyword introducing semi-rigid connection data.. ax ay . Keyword introducing stiffness about member z axis of spring at "A". Keyword introducing stiffness about member z axis of spring at "B". Name of library file. The geometric properties about the principal axes of the member cross-section are specified. Keyword introducing stiffness about member y axis of spring at "B". Keyword introducing stiffness about member y axis of spring at "A". Stiffness value. Stiffness value. The file name including extension must LIBR lib_name 192 • 10:Macro Language Input Microstran V9 . Stiffness value. Stiffness value. Keyword. Labels introducing section property value. List of members with specified section properties. are not used.
See "Section Properties" on page 88. The file name extension ". Materials must be defined for all members. Keyword. If the keywords E. and ALPHA are not used in the PROP statement. See "Material Properties" on page 92. Name of library file. Materials Group MATERIALS list PROP E e PR pr DENS dens ALPHA alpha or list LIBR lib_name matl_name where: list PROP E e PR pr DENS dens ALPHA alpha lib_name List of members with specified material properties. The file name including extension must not exceed 16 characters. Microstran V9 10:Macro Language Input • 193 . the property values must be given in the above order. Label introducing coefficient of thermal expansion.not exceed 16 characters. Label introducing mass density value. the first material in the library whose name matches the abbreviation will be selected. sect_name Name of section. PR. the first section whose name matches the abbreviation will be selected. Poisson's ratio. Label introducing Young's modulus value. The file name extension ". Label introducing Poisson's ratio value. Any omitted properties are set to zero. Name of material. Mass density. Coefficient of thermal expansion. DENS. Abbreviations may be used. matl_name This data group is used to specify material properties of members. Abbreviations may be used.lib" will be added if no extension is specified. Young's modulus.lib" will be added if no extension is specified.
fx fy . Several different load types may be included in each load case.. MX MY . Node force values. Acceleration Group GRAVITY LOADS GX gx GY gy GZ gz where: gx gy gz Acceleration in global X direction. up to 50 characters. Examples: NODE LOADS 1 2 3 TO 9 INC 2 FX -1.. Acceleration in global Z direction. See "Node Loads (NDLD)" on page 102. Labels introducing fx fy etc. These are set out below. mx my .2 OTHERS FZ 5. Node Loads Group NODE LOADS list FX fx FY fy FZ fz MX mx MY my MZ mx where: list FX FY . Description or load case title. Acceleration in global Y direction.. Labels introducing mx my etc. See "Acceleration Loads (GRAV)" on page 102.1 194 • 10:Macro Language Input Microstran V9 . Node moment values.. Case Statement CASE lcn desc where: lcn desc Load case number.Load Block Each load case commences with a CASE statement and is terminated either by the CASE statement for the next load case or by the END statement that marks the end of the MLI file. List of nodes to which the loads are applied.
5 Node Temperatures Group NODE TEMPERATURES list TEMP t where: list t List of nodes to which the specified temperature differential applies. Distance from end "A" to start of load. Keywords for numerical parameters may be omitted if load values are given in the above order. CONC. FZ. UNIF. May be omitted for UNIF and TRI1 loads.1 121 122 123 TRAP FY LO FR F1 1. See "Member Distortions" on page 107. LE or FR. list DIST {FX | . F2 2. MY. Distance from end "A" to end of load. Keywords introducing x1 x2.g. TRI1 or TRI2. FY. Node temperature differential..1 X2 1 145 CONC FY GL FR -10. See "Member Loads (MBLD)" on page 103. or MZ. Keywords introducing f1 f2. See "Node Temperatures (TEMP)" on page 109.5 . UNIF loads require f1 only). Magnitude at start of load. Depending on the load form. TRAP. some of the numerical values shown in parentheses may be omitted (e. FX.. MX.1 X1 0.Member Loads Group MEMBER LOADS list form type axis scale F1 f1 [X1 x1 [F2 f2 X2 x2]] where: list form type axis scale F1 F2 f1 f2 X1 X2 x1 x2 List of members to which the load is applied. | MZ} {LE | FR} F1 f1 X1 x1 Examples: MEMB LOADS 101 TO 199 INC 2 UNIF FY GL -2. Magnitude at end of load. GL or LO. Microstran V9 10:Macro Language Input • 195 . Member Distortions Member distortions may be defined as member loads with the load form keyword DIST.
196 • 10:Macro Language Input Microstran V9 . dx dy .Member Temperatures Group MEMBER TEMPERATURES list TEMP TX tx TY ty TZ tz where: list tx ty tz List of members to which the specified temperature applies. rx ry ... Labels introducing dx dy etc. Prescribed Displacements Group NODE DISPLACEMENTS list FX dx FY dy FZ dx MX rx MY ry MZ rz where: list FX FY . MX MY . Centroidal temperature differential. List of nodes at which the displacements are prescribed. Effective temperature gradient in member z direction.. See "Prescribed Node Displacements (NDIS)" on page 111.. See "Member Temperatures (MTMP)" on page 110. Prescribed rotation values (radians). Effective temperature gradient in member y direction. Prescribed displacement values. Labels introducing rx ry etc.
the MLI data and appropriate error messages will be written to the error log. Factor by which load case is multiplied before adding to combination load case. END Statement END The last statement in an MLI file contains the keyword END.Combination Load Case Group COMBINATION lc1 f1. Load case number for a previously defined load case. . the data line that caused the error will be listed with the error message. lc2 f2. Microstran V9 10:Macro Language Input • 197 . either syntax errors or missing data.. After detecting an error the program proceeds with syntax checking but if more than ten errors are found checking will cease and the remainder of the input file will be listed in the error file. The new load case is then: lc = f1 × lc1 + f2 × lc2 + … + fn × lcn Load cases containing combinations must not contain any other load types and must be defined after all primary load cases have been specified. . lcn fn where: lc1 lc2 . See "Combination Load Cases (COMB)" on page 114.. f1 f2 . For syntax errors... MLI Errors If any errors are found in the MLI file.
LIB 219.MLI Example The MLI file listed below generates a spiral staircase structure as shown in the diagram.1x6. 0.1 CASE 3 Case 1 + Case 2 COMB 1 1.LIB 250x150x6. 0. 0. 30.LIB STEEL CASE 1 Dead Load GRAVITY LOADS GZ -9.2 END MLI EXAMPLE – SPIRAL STAIRCASE 198 • 10:Macro Language Input Microstran V9 .1 MEMB LOADS 1 TO 12 UNIF FZ GL -1.LIB 150x100x6.0RHS $ Treads MATERIAL ALL LIBR MATL. .4 $ Spine (INC 1) SUPPORTS 1 13 FIXED 41 53 PINNED MEMBER INCIDENCES 1 1 2 TO 12 $ Spiral (INC 1 1 1) 41 41 42 TO 52 $ Spine (INC 1 1 1) 101 1 41 TO 113 $ Treads (INC 1 1 1) REFERENCE NODE 1 TO 12 .8 CASE 2 Tread Loads NODE LOADS 1 TO 12 FZ -2. 0. 2. $ Start of spiral REP 12 INC 1 0. 2 1.0RHS $ Spiral 41 TO 52 LIBR ASW. 0.4CHS $ Spine OTHERS LIBR ASW. TITL1 Spiral Stair TITL2 MLI Example UNITS kN m t C TYPE SPACE FRAME VERT Z NODE COORDINATES CYLIND 1 4. TO 53 0.2 $ Generate spiral 41 0. . 101 TO 113 AXIS Z OTHERS AXIS X MEMBER PROPERTIES 1 TO 12 LIBR ASW.
Options are available to apply loads automatically to continuous beams or grillages in the Microstran model. longitudinal loads. You will then be prompted to select the load-carrying members of the Microstran V9 11:Moving Load Generator • 199 . Generating the Loads Loads are specified in a file that is edited with the text editor. To generate the required loads. The direction of the moving load is generally along the global X axis for loads on beams and along a lane for loads on grillages. and lateral line loads. Multiple load cases can be specified and new loads can be generated automatically to represent the movement of a specified load pattern across the structure. DECK1 EXAMPLE – T44 TRUCK LOADINGS ON CURVED BRIDGE DECK Available load types include fixed distributed and concentrated loads. area loads. truck loadings (for standard trucks and user-defined trucks). select the Loads > Moving Loads > Beam command or the Loads > Moving Loads > Grillage command. The specification of lanes is discussed below. The file is created for you automatically if it does not exist when you begin the generation process.11:Moving Load Generator General This optional module may be applied to any Microstran model and is particularly useful for generating service loads on bridge structures. lane loads. Assumptions • • Grillage models must have the global Z axis vertical (all loads are generated as global Z loads). The text file may be edited "from scratch" but it is usually easier to begin with a template file.
HLP400 – AUSTROADS Heavy Load Platform loading. either "F" or "B". SVnnuuuD – Malaysian JKR SV loading. Select the members. and D is the direction the truck. 200 • 11:Moving Load Generator Microstran V9 . Once you confirm the members to be loaded. Truck Types A number of standard truck types are built into the program and may be referenced by name. nn is the number of axles in the SV trailer. Where other types of load. SV20007F represents a forward-facing SV truck with a twenty axle trailer with each axle of the trailer having a weight of 70 kN. T54F. For example. uuu is the number of 10 kN units of loading in each of the trailer axes.beam or grillage. Definition of special loads. HLP320. Definition of base load cases of various types. The suffixes F and B are used to position the truck facing forwards or backwards with respect to the positive lane direction. Making a set of the required members will facilitate their rapid selection. nm is the number of units of HB loading (10 kN/axle) to be applied. the current load definition file will be displayed in Microstran's text editor window. the overall length of the truck is 21 meters. Generally the file consists of: • • • • Definition of the areas or lanes to be loaded (grillages only). The variable spacing is checked for compliance with the values specified in BS 5400. or in the range from 6 to 15 meters. The formats used for beams and grillage files differ and are described in the following pages. are involved they can be combined as a base load case and then used to generate moving loads in subsequent load cases. If you have not already created a load file the editor will display a standard template file. HBnm – BS 5400 HB loading. Standard loadings are available for the following trucks: • T44F. such as knife-edge or area loads. and confirm the selection. T44B – AUSTROADS T44 truck loading. whose format depends on whether you have selected beam or grillage loading. The variable spacing is either 0. T54B – Semi-trailer/B-double truck. Specification that generates load cases by incrementally positioning the base load cases. right-click. • • • • You may define trucks other than the standard trucks by making up a group of point loads using the TRUCK command. The suffixes F and B are used to position the truck facing forwards or backwards with respect to the positive lane direction. The axle spacing of the semitrailer may be varied from 3 to 8 meters.
The reference point for user-defined trucks is the origin of the truck coordinates. The first diagram shows one position of a T44F truck on a 2-span bridge. and the centroid of the load group for HLP and HB loadings. Beam1. The reference point for standard trucks on beams is the axle furthest from the start of the beam. which are convenient when dealing with moving loads. which is included in the examples folder when you install Microstran. each corresponding to a different location of the truck. Microstran permits the display and reporting of member force envelopes. Example The diagrams below illustrate the example.The reference point for positioning standard truck loadings on grillages is the central point load for T44. The second shows the bending moment diagram for all generated load cases. BEAM1 EXAMPLE – T44F TRUCK BEAM1 EXAMPLE – BM DIAGRAM FOR ALL TRUCK POSITIONS Microstran V9 11:Moving Load Generator • 201 .
The load intensity at the start of the WUDL load. This allows a logical arrangement of the load data in the BBL file with full control over the number of load cases to be analysed. The load type and OFFSET statements are described below.. Comments may be included after the "$" character. Load case title. It is fixed in position and cannot be moved as part of an OFFSET load case. The length of the load. Keyword that specifies output of this load case to the Microstran job.. each truck could be assigned to a separate load case but output could be restricted to those combinations with individual cases having a particular offset. if an assessment has to be made of the effects of trucks in different spans of the bridge. WUDL distance length w1 w2 where: Distance Length w1 w2 The distance from the start of the beam to the nearest end of the load. 202 • 11:Moving Load Generator Microstran V9 . Load case number.. Load positions on beams are determined from the start of the beam.. The load intensity at the end of the WUDL load.. which is the end of the selected sequence of members having the smallest X coordinate. up to 50 characters.. .BBL. For example.. END where: CASE N Title OUTPUT Keyword marking start of new load case. Load Types – Beams Fixed Distributed Load – Beams: This is a distributed load of constant or varying magnitude. which may lie on a curve having both vertical and horizontal curvature. The load file is a text file named Job.. . CASE n title [OUTPUT] [Load type statements] [OFFSET statements] CASE.Moving Loads – Beams Moving loads are applied to a series of connected beams.. It consists of one or more CASE blocks followed by an END statement.. where "Job" represents the job name.
The first x value is conventionally zero. Microstran V9 11:Moving Load Generator • 203 . TRUCK name x P . Coordinate and load value.. Line Load – Beams: This is a distributed load of constant magnitude.. . Point Load – Beams: This is a point load that may be moved along the beam as part of an OFFSET load case.. used to locate its axles... It may be moved along the beam as part of an OFFSET load case. Load per unit length. LINEL distance length load where: distance length load The distance from the start of the beam to the nearest end of the load... POINT distance load where: distance load The distance from the start of the beam to the load. Each user-defined truck has its own coordinate system. CONC distance load where: distance load The distance from the start of the beam to the load. The value of the CONC load. User-Defined Trucks – Beams User-defined trucks or other point load groups may be defined as a table of coordinates and load values.. The value of the POINT load. Length of line load. A number of (x P) groups may be entered on each line.Fixed Concentrated Load – Beams: This is a concentrated load. END where: name x P Character string of one to eight characters used to identify the load group. It is fixed in position and cannot be moved as part of an OFFSET load case.
Factor applied to truck loads (e. impact factor).Truck Loading – Beams: The group loading can be used for standard trucks or user-defined trucks that have been previously defined with a TRUCK statement. Ignored if not applicable (e. Truck name of a standard or user-defined truck. A group load may be moved along the beam as part of an OFFSET load case.g. Standard truck loading parameter. GROUP distance truck var_space factor where: distance The distance from the start of the beam to the load origin. user-defined truck).g. truck var_space factor T44F TRUCK LOADING T44B TRUCK LOADING 204 • 11:Moving Load Generator Microstran V9 . The load origin for a standard truck is the axle furthest from the start of the beam.
These parameters are the same for all OFFSET statements in any CASE block and they may be omitted for all but the first OFFSET statement in each CASE block. May be zero if noff is zero. Load case number increment for additional generated load cases. Microstran V9 11:Moving Load Generator • 205 . OFFSET lcase start inc [ noff lc_inc ] [F f] where: lcase start inc Number of previously defined load case to be offset. Any load case containing offset cases must not itself be offset. WUDL and CONC loads are fixed and will not be offset if included in a load case referred to by an OFFSET statement. There may be more than one OFFSET statement in each CASE block. Zero if only one new load case is required.Offset Load Cases – Beams New load cases may be generated by offsetting previously defined load cases with the OFFSET statement. noff lc_inc F f No other load type may be included in a CASE block containing an OFFSET statement. whose number is the number on the preceding CASE statement. Keyword to specify factor for the offset load case. Number of offset cases to be generated. May be zero if noff is zero or if all generated loads are at the same location. A series of additional load cases is generated according to the parameters. Offset distance of first load case from base load case. lcase. Factor applied to generated loads. Each generates at least one load case. apart from the first. noff and lc_inc. Incremental distance along beam for each additional generated load case.
0 $ lcase start inc CASE 150 Move truck along bridge OUTPUT OFFSET 1 0.0 1.0 2.0 0. The diagrams on page 201 show the structure and the bending moment diagram resulting from the CASE 150 block.0 $ distance CASE 2 Fixed UDL on span 2 $OUTPUT WUDL 20 40 -25 -25 $ distance CASE 3 Fixed conc.0 1.0 24 1 $ lcase CASE 200 Move UDL along bridge $OUTPUT OFFSET 4 -10.Example – BBL File 2-Span Bridge as Beam CASE 1 Truck at start of bridge $OUTPUT GROUP 0 T44F 3. this example is included in the examples folder as Beam1.0 2.0 24 1 $ lcase END start inc noff lc_inc start inc noff lc_inc On installation of Microstran. load on span 1 $OUTPUT CONC 15 -25 $ distance truck var_space factor length w1 w2 load CASE 4 Movable UDL at start of bridge $OUTPUT LINEL 0 10 -30 $ distance length load CASE 100 Move truck along span 1 $ Note fixed UDL on span 2 for all generated cases $OUTPUT OFFSET 1 0.0 20 1 $ lcase start inc noff lc_inc OFFSET 2 0. 206 • 11:Moving Load Generator Microstran V9 .
HBL.. Lanes are paths along which loads may be moved. END r1 r2 $ start segment 1 $ end segment 1..Yn).. LANE... There is one LANE block for each lane. -ve = curves to right. Lane number.. 0 = straight. together with widths and radii of curvature. Global coordinates of point defining start or end of a segment..Yn) – required for distributed or fullwidth line loads. Lane Definition A lane must be defined for all types of loading except UDL and AREA loads. otherwise not significant. Loads are defined in a text file named Job. where "Job" represents the job name. . . Grillage loadings are located by reference to lanes or areas.Moving Loads – Grillages Moving loads may be applied to a grillage of members. Each is defined as a sequence of straight and curved segments by inputting centre-line coordinates. LANE lane X1 Y1 w1 X2 Y2 w2 . start segment 2 where: LANE lane Xn Yn w r Keyword marking start of new lane. Radius of curvature of segment starting at (Xn.. Comments may be included after the "$" character... +ve = curves to left. Width of lane at (Xn. LANE DEFINITION Microstran V9 11:Moving Load Generator • 207 .. followed by an END statement. provided that no members of the grillage cross without intersecting...
.. For example.. each truck could be assigned to a separate load case but output could be restricted to those combinations with individual cases having a particular offset.. . There is one AREA block for each area. Load case title.. END where: CASE n title OUTPUT Keyword marking start of new load case. END where: AREA na Xn Yn Keyword marking start of new area.. Load Cases – Grillages The load section of the HBL file consists of one or more CASE blocks followed by an END statement. each of which is Microstran V9 gmax 208 • 11:Moving Load Generator ... Load case number.... CASE n title [OUTPUT] GMAX gmax [Load type statements] [OFFSET statements] CASE. Keyword that specifies output of this load case to the Microstran job. Area number. each of which is at the midpoint of a short line segment whose length is equal to or slightly less than gmax.. A line load is modelled as a set of point loads.Area Definition Areas are defined by a list of points bounding the area to which AREA or UDL loads are applied.. ... . A dimension that controls the modelling of distributed loads as sets of point loads. AREA na X1 Y1 X2 Y2 .... up to 50 characters. This allows a logical arrangement of the load data in the HBL file with full control over the number of load cases to be analysed...... Global coordinates of point on boundary of area.. followed by an END statement. . An AREA load is modelled as a set of point loads. AREA. if an assessment has to be made of the effects of trucks in different spans of the bridge.
The load type and OFFSET statements are described below. Load Types – Grillages Overall Load – Grillages: WUDL load Load per unit area over whole grillage.centred on a rectangle with sides equal to or slightly less than gmax. The recommended value of gmax is about 25% of the minimum grid spacing.. Lateral distance of load from lane centre-line – a positive value indicates that the offset is to the left of the centre-line when looking in the direction of increasing distance. The load value. Distance along the lane centre-line from the lane origin to the load. Once defined. offset load where: lane distance offset load POINT LOAD Microstran V9 11:Moving Load Generator • 209 . the value of gmax is retained for subsequent load cases until the next GMAX statement. where: load Point Load – Grillages: POINT lane distance Lane number.
Load per unit length.Full-Width Lane Load – Grillages LANEL lane distance Lane number. offset length load where: lane distance offset length load LONGITUDINAL LINE LOAD 210 • 11:Moving Load Generator Microstran V9 . Lateral distance of load from centre-line – a positive value indicates that the offset is to the left of the centre-line when looking in the direction of increasing distance. Distance along the lane centre-line from the lane origin to the centre of the load. Length of load. Distance along the lane centre-line from the lane origin to the centre of the load. Load per unit area. Length of load. length load where: lane distance length load FULL-WIDTH LANE LOAD Longitudinal Line Load – Grillages LINEL lane distance Lane number.
.. Distance along the lane centre-line from the lane origin to the centre of the load. TRUCK name x y P .Full-Width Lateral Line Load – Grillages: KNIFE lane distance Lane number.. Load per unit area. load where: lane distance load FULL-WIDTH LATERAL LINE LOAD Area Load – Grillages AREAL area load Area number. Coordinates and load value. The truck origin is the point that is the origin of the truck coordinate system. END where: name x y P Character string of one to eight characters used to identify the load group. Load per unit length. used to locate its wheels. where: area load User-Defined Trucks – Grillages User-defined trucks or other point load groups may be defined as a table of coordinates and load values... . A number of (x y P) groups may be entered on each line.. The truck is positioned along a lane with its positive x axis parallel to the lane centre-line and in the direction of increasing distance along the lane.. Microstran V9 11:Moving Load Generator • 211 .. Each user-defined truck has its own x-y coordinate system.
800 -4.000 0.hbl file below contains the coordinates of each wheel with respect to the centre of the front axle.900 -1.5 28 1 END HBL FILE 212 • 11:Moving Load Generator Microstran V9 .900 0.000 -3. LANE 1 -5 -1.5 0.85 3.0 0. The OFFSET statement creates 28 new cases.000 END -24 -24 -24 -24 -24 -24 -24 -24 -24 -24 $ $ $ $ $ $ $ $ $ $ front left front right middle left outer middle left inner middle right inner middle right outer rear left outer rear left inner rear right inner rear right outer CASE 1 MyTruck .900 1.Base case OUTPUT GMAX 0.900 -3. Each wheel load is 24 kN.900 0.700 1.800 -3.5 m along the bridge.7 0 15 -1.85 3. USER-DEFINED TRUCK IN LANE The .User-Defined Truck Example The diagram below shows each wheel of a user-defined truck positioned on the centre-line of a lane 3.800 -4.900 -0.000 -4.700 -1.700 0.7 m wide with the front axle adjacent to the global origin.800 -3. Any point could be used but using a point on the centre-line of the truck means that the lateral offset dimension on the GROUP statement is zero when the truck is on the lane centre-line. each with the truck moved 0.000 -4.25 GROUP 1 5.7 0 END TRUCK MyTruck 0.700 -0. This establishes the truck origin at that point.000 -0.0 MyTruck 0 1 CASE 2 MyTruck OUTPUT OFFSET 1 0.
impact factor).g. offset truck var_space factor where: lane distance offset truck var_space factor T44F TRUCK LOADING Microstran V9 11:Moving Load Generator • 213 .g. user-defined truck). Distance along the lane centre-line from the lane origin to the origin of the group or truck load.Truck Loading – Grillages: GROUP lane distance Lane number. Ignored if not applicable (e. Truck name – either standard truck name or user-defined truck name. Standard truck loading parameter. Lateral distance of truck origin from centre-line – a positive value indicates that the offset is to the left of the centre-line when looking in the direction of increasing distance. Factor applied to truck loads (e.
whose number is the number on the preceding CASE statement. 214 • 11:Moving Load Generator Microstran V9 . Incremental distance along centre-line for each additional generated load case. For areas with more than four distinct vertices. For a rectangular grid this gives a set of triangular and trapezoidal loads along the short and long members respectively. the load is allocated by bisecting the angles between adjacent members. LINEL. Lane loads that have a lateral offset value (POINT. No loads will be allocated to any cantilevers. These parameters are the same for all OFFSET statements in any CASE block and they may be omitted for all but the first OFFSET statement in each CASE block. Starting distance along centre-line for loads in lcase. May be zero if noff is zero or if all generated loads are at the same location. There may be more than one OFFSET statement in each CASE block. Load case number increment for additional generated load cases. OFFSET lcase start inc [ noff lc_inc ] [F f] where: lcase start inc Number of previously defined load case to be offset. area loads. WUDL and CONC loads are fixed and will not be offset if included in a load case referred to by an OFFSET statement. Number of offset cases to be generated. May be zero if noff is zero.Offset Load Cases – Grillages New load cases may be generated by offsetting previously defined load cases with the OFFSET statement. noff lc_inc F f No other load type may be included in a CASE block containing an OFFSET statement. Factor applied to generated loads. Keyword to specify factor for the offset load case. and GROUP loads) may be applied anywhere across the grillage. Where these are the only loads applied. not necessarily within the defined lane width. Each generates at least one load case. Any load case containing offset cases must not itself be offset. For areas enclosed by three or four members. Overall UDLs are applied as a series of linearly varying distributed member loads. Zero if only one new load case is required. and line loads are modelled with statically equivalent point loads applied to the nodes of adjacent members. noff and lc_inc. Distribution of Loads to Grillage Point loads. A series of additional load cases is generated according to the parameters. uniform loads are applied to each bounding member. and the grillage must not contain members that cross without intersecting. apart from the first.
0 120 479.0 0 530.171 567.260 500.875 T44F 3.0 $ lane distance offset truck var_space factor CASE 5 T44F s=60 $OUTPUT GMAX 0.571 3.0 0 466.948 570.0 $ lane distance offset truck var_space factor CASE 6 Two trucks 40L 105R OUTPUT OFFSET 1 15 0 0 0 $ lcase start inc noff lc_inc OFFSET 2 0 0 $ lcase start inc CASE 7 Two trucks 60L 85R OUTPUT OFFSET 1 35 0 0 0 $ lcase start inc noff lc_inc OFFSET 2 -20 0 $ lcase start inc $CASE 8 Two trucks 80L 65R $ OUTPUT $ OFFSET 1 55 0 0 0 $ lcase start inc noff lc_inc $ OFFSET 2 -40 0 $ lcase start inc END On installation of Microstran.0 0 527.5 $ spacing of output point loads GROUP 1 60 1.133 461.301 3.g.440 3. The diagram on page 199 shows the structure and the generated loads.0 1.875 T44F 3.875 HB40 6. only a single lane definition is required (e.710 3.875 T44B 3.245 3.664 577.0 0 529.5 $ spacing of output point loads GROUP 1 25 1. the bridge centre-line).645 3.0 0 531.800 3.and all potential lanes are parallel. this example is included in the examples folder as Deck1.0 0 END $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ start of lane s=0 start of deck s=25m 120m radius to next point end of deck s=150m end of lane s=175m CASE 1 T44F s=25 (start of deck) $OUTPUT GMAX 0.793 485.273 3.618 572.0 0 433.0 0 528.061 497.830 3. Microstran V9 11:Moving Load Generator • 215 .116 3.552 502.0 $ lane distance offset truck var_space factor CASE 2 T44B s=105R $OUTPUT GMAX 0.0 1.804 3.187 575.916 588.185 3.534 495.0 0 461.259 488.0 0 530.0 1.056 579. Example – HBL File Curved Bridge Deck LANE 1 $ Deck centre-line $ X Y Width Radius 537.0 $ lane distance offset truck var_space factor CASE 3 KNIFE LOAD s=25 (start of deck) $OUTPUT KNIFE 1 25 -50 $ lane distance load CASE 4 HB40 s=130 $OUTPUT GMAX 0.0 0 529.129 493.5 $ spacing of output point loads GROUP 1 130 -1.624 3.406 3.5 $ spacing of output point loads GROUP 1 105 -1.0 1.0 0 474.0 0 457.704 490.0 0 531.143 3.400 3.0 0 470.
216 • 11:Moving Load Generator Microstran V9 . then select the load-carrying members of the grillage. Press the space bar to show the next lane. Note: Making a set of the grillage members to be loaded allows them all to be selected from the Current Set pull-down in the View toolbar. allowing sufficient runoff for trucks. To generate the required loads. The steps required to run a simple example are shown below. A small skew grillage has been defined with an existing load case and load combinations are to be generated.Moving Loads Graphics An optional graphical interface is available to simplify the input of data for moving loads on a grillage. select the Loads > Moving Loads > Grillage command. Step 1 – Specify lanes Use the Loads > New Lane or Loads > Edit Lane command to specify the lanes. The Loads > Display Lanes command can now be used to see the lane centre-lines superimposed on the grillage.
Step 2 – Specify user-defined truck Use the Loads > New Truck or Loads > Edit Truck command to specify user-defined trucks as required. The dialog box below shows the specification of a truck named T60. Step 3 – Set up M1600 trucks at the start of lanes 1 and 2 Use the Loads > New Load Case command to specify primary load cases 10 and 11 with standard M1600 trucks at the start of lanes 1 and 2. Microstran V9 11:Moving Load Generator • 217 . respectively.
Then. a forward-facing M1600 truck) at the start of lane 1. the user-defined truck at the start of lane 3. 218 • 11:Moving Load Generator Microstran V9 .In the case definition dialog box click the Add button to specify loads. specifying an M1600F truck (i.e. Step 4 – Set up user-defined truck at start of lane 3 Define primary load case 12. in the Add Moving Load dialog box select a GROUP load.
Primary load cases 100 to 180 will be generated. The offset data for case 11 is specified in the small dialog box and it will appear in the list box when the OK button is clicked. Offset data for case 13 is input similarly. In the image below the offset data for case 10 has been input and it is shown in the list box. Click the Add button in the case definition dialog box to specify the cases that are going to be offset.Step 5 – Specify offset load case to move trucks across grillage Use the Loads > New Load Case command to define offset load case 100 to move all the trucks across the grillage. For each case the starting distance and the offset data are specified. Microstran V9 11:Moving Load Generator • 219 .
In the image below the combination data for case 1 has been input and it is shown in the list box.Step 6 – Specify combination load cases Use the Loads > New Load Case command to define combination load case 500 as a combination of case 1 with a factor of 1. Combination load cases 500 to 580 will be generated using case 1 and offset cases 100 to 180. 220 • 11:Moving Load Generator Microstran V9 . Click the Add button in the case definition dialog box to specify the combinations.5.25 and offset case 100 with a factor of 1. The combination data for case 100 is specified in the small dialog box and it will appear in the list box when the OK button is clicked.
Select the Drive command again to stop the moving loads display. Step 8 – Display applied loads Use the Loads > Display Applied Loads command to show the loads one case at a time. On selecting the Loads > Process Applied Loads command these instructions are executed. the trucks advancing along their lanes. generating new load cases in the Microstran database.e. i. Select the Loads > Drive command to show all cases cyclically. The first load case is shown. press the space bar to advance to the next case. Microstran V9 11:Moving Load Generator • 221 .Step 7 – Process applied loads The data input in the foregoing steps is automatically stored as instructions in the HBL file. This gives the appearance of the loads moving.
222 • 11:Moving Load Generator Microstran V9 . Original load cases that are not included in the HBL file may be retained. Step 10 – Update Microstran Loads Close the Movload window by selecting the File > Exit command or clicking the X button at the top right corner. you may display the loads on the grillage by using the Loads > Display Applied Loads command.Step 9 – Distribute loads to grillage The Loads > Distribute Loads to Grillage command calculates and applies loads to the nodes in the grillage. As in the previous step. The Microstran window should now be visible with the Load Case Options dialog box displayed.
The image below shows the bending moment diagram for all the combination load cases.The Microstran database should now include the loads generated by the Movload module and the updated model may be analysed. Microstran V9 11:Moving Load Generator • 223 .
224 • 11:Moving Load Generator Microstran V9 .
msw is not listed browse to your Microstran data folder where you should find this file.msw. and how loads can be changed graphically. Input data. "Selecting Nodes and Members". You should now see the portal frame displayed in the Microstran window. select Open. Step 1 – Start Microstran. Maximize the Microstran window if it is too small. and "Right-Clicking on Nodes and Members". Refer to Chapter 2 – "Getting Started" for an explanation of Microstran basics. select Programs and then Microstran. select Ex2. You can download these and view them on your computer if you wish. "Microstran Commands" on page 21. Step 2 – Open a file. in the form of an archive file. results and diagrams for this example are included in Chapter 20 (see "Example 2 – Portal Frame" on page 345). for example. the input data for this job will exist in your data folder. select Import. After installing Microstran successfully. the portal frame example included on the distribution diskettes is run to demonstrate analysis. Click the Display Node Numbers and Display Member Numbers buttons on the Display toolbar at the top of the window and notice the display change. Tutorial 1 – Running an Existing Job In this tutorial. Click on the Windows Start button. from the listed files and click on the Open button. Some of the tutorial examples are available from the Microstran website as self-playing Lotus ScreenCam demo files. screen plots. Microstran V9 12:Input Tutorials • 225 . "Cursors". Select File on the menu bar. If Ex2.12:Input Tutorials This chapter contains several tutorial examples to show you how to go through all the steps needed to do a typical job.
Click on the Display Applied Loads button at the top of the Results toolbar on the left of the main window. Select Loads on the menu bar. Notice that the bending moment diagram is redrawn with the new scale factor. 2. Step 5 – Display bending moment diagrams. Select Results on the menu bar. notice bending moment values now displayed on the bending moment diagram. Click on the Display Results Values button on the Display menu. When in load input mode the current input case is displayed automatically. deselect the primary load cases and select case 5. click on OK. Step 6 – Change scale of plot (optional). Close the analysis window by clicking on the X button at the top right of the window. select Select Input Case. click on Display Options. exactly as it was shown in the print preview. Step 8 – Change the value of a load. click on the OK button and notice that the loads are now displayed. In the list box showing the load cases titles select cases 1. click the right mouse button. Type any desired title for the view in the dialog box. Click on the Print View button on the main toolbar. click on the OK button in the dialog box. select Member Loads. notice the graphics preview display. and 4 (the primary load cases). Select View on the menu bar. Notice that the load on member 3 has now 226 • 12:Input Tutorials Microstran V9 . Notice that the loads are displayed for case 4 even though the Display Applied Loads button is not depressed.Step 3 – Analyse the structure. Click on the Print Preview button on the main toolbar. Click on the Display Applied Loads button again to turn off the load display. Select Analyse on the menu bar. click on the Scales tab of the Display Options property sheet. To display the values at the extremities of the plot you may have to click on the Zoom Out button. Select Delete Load on the Load menu. select Select Load Cases. Turn off the bending moment display by clicking on the Bending Moment Mz button again. type 2. Applied loads are not shown for combinations. click on the OK button. click on case 4. The view should now print on the default printer. It should be very similar to the examples in Chapter 20. click on the Bending Moment Mz button. You should see the message "Linear analysis completed" at the bottom of the window. select Linear. press the Tab key until the Bending moments scale is selected. 3. click OK on the context menu (this confirms selection of member 3). press Enter. right-click to terminate the command. If the bending moment diagram does not fit within the window click on the Zoom Out button on the View menu. click on the Close button. click on member 3. Notice a new window open as the analysis module performs the analysis. Step 7 – Preview a plot and print it. Step 4 – Display applied loads. the right rafter.
and display the results. check that Type is FY and that Axes are Local. click on OK. Step 3 – Draw left-hand column and a horizontal rafter. analyse the structure. Click on the Windows Start button. In the dialog box click on the Yes button to save the job. click on OK or press Enter. Check that the Plane frame and Y axis option buttons are selected. type a value of -2. Click on the X button at the top right of the Microstran window. °C for units if not already selected. The structure and loads are shown in the diagram above.5 in the F1 = edit box. Click on the Draw Members button (the one with the pencil). select sections and material. type "0" or "0. Select New on the File menu or click on the New Job button. Select the Loads > Member Loads command. move the mouse right Microstran V9 12:Input Tutorials • 227 . move the mouse to draw a vertical member 4 m high and then click. titles etc. type "TUT2" for the job name (do not include the quotes). click on the OK button or press Enter. select Programs and then Microstran. Notice also that the buttons on the Results toolbar have become greyed out because the analysis results were invalidated when the load data changed. Type a job title and press Enter. Select m. click on the uniform load in the dialog box. Maximize the Microstran window if it is too small.disappeared. click OK to accept the default job file folder. click on OK. Step 1 – Start Microstran. right-click to terminate the command. kN. click on the Front View button on the View toolbar at the top of the window. Tutorial 2 – Running a New Job TUTORIAL 2 This tutorial takes you through the steps needed to input a structure and loads graphically. confirm the selection after right-clicking. t. Step 2 – Set the job name. click on member 3.0" and then press Enter. Click on the Snap to Grid button on the Draw toolbar at the right of the main window. Step 9 – Exit Microstran. Notice the new load on member 3.
check that the axis of rotation is Z. and press Enter. click on both members. TUTORIAL 2 – STEP 4 Step 5 – Reflect column and rafter. click the right mouse button and on the context menu select End Line. click on OK or press Enter. Right-click to terminate the command. press Enter. Click on the Reflect button. and on the context menu select OK. TUTORIAL 2 – STEP 5 228 • 12:Input Tutorials Microstran V9 . click on any grid point 6 m to the right of the column. check that the normal axis is X and that the Extrude nodes box is not checked. right-click.to draw a horizontal member 8 m long and then click. Click on the Rotate button. click on the horizontal member. right-click and click on OK. click on the top left node (the centre of rotation). TUTORIAL 2 – STEP 3 Step 4 – Rotate rafter 15°. Right-click to terminate the command. type "15" for the angle.
0). Member axes. click on the Nodes tab. Step 9 – Input supports. Click on the Members tab and check the boxes for Member numbers.) Microstran V9 12:Input Tutorials • 229 . Click on the Draw Members button. select the View > Redraw command. click on the apex node.Step 6 – Draw central column. Node symbols. click on the pinned support button and then on the OK button. TUTORIAL 2 – STEP 7 Step 8 – Display attributes. right-click and select OK on the context menu. click on point (6. Select the View > Display Options command. click in the check boxes for Node numbers. (Instead of using the menu item. Click on the OK button and notice these items now displayed in the view. Notice the symbols now displayed at the support nodes. right-click and select End Line on the context menu. click on each rafter overhang. click on each of the three support nodes. referring to the coordinate readout in the status line at the bottom right of the window. Click on the Erase Members button. and Pins. Right-click to terminate the command. Select the Structure > Attributes > Fixed Supports command. TUTORIAL 2 – STEP 6 Step 7 – Trim overhangs on rafters. right-click and then click the OK button. and Supports. you could have clicked on the Input Supports button on the Attributes toolbar. click on the Snap to Intersection button on the Draw toolbar at the right of the window. right-click to terminate the command.
Select the Library option button and click on Input/Edit.TUTORIAL 2 – STEP 9 Step 10 – Input pin at top of central column. select a 200 mm UB section. Using the above method input a 200 mm UB for the central column. right-click to terminate the command. Notice the small circle plotted at the top of the central column to represent the pin. Click on the OK button in the Section dialog box. input "3" for the section number and click on OK. right-click to terminate the command. TUTORIAL 2 – STEP 10 Step 11 – Input section numbers. click on the button with the horizontal pin axis in the End "B" group. Select a 300 mm UB section. Notice that the rafters are now highlighted (section 2). click on the central column. Click on the Input Section Number button on the Attributes toolbar. Step 12 – Input sections from library. right-click and select OK. right-click and select OK. select the View > Redraw command. 230 • 12:Input Tutorials Microstran V9 . Notice the colours of the rafters and the central column have changed to represent the new section numbers. Click on the Legend tab of the output window at the bottom of the main window and notice the key to the colours of the sections. click on OK. Click on the Input Section Properties button on the Attributes toolbar. click on the up spin button so the section number becomes "2" and click on OK. click on OK. double-click on UB. click on the central column. click on each rafter. right-click. click on the OK button in the Section dialog box. Notice the columns (section 1) highlighted. Click on the Input Releases button on the Attributes toolbar.
right-click and select OK on the context menu. The results are now displayed for this member. click on the right-hand rafter. Click on the right rafter and notice the results in the Query page of the output window at the bottom of the main window. Click on the OK button in the Material dialog box. Step 17 – Use query function to display results numerically. right-click and select OK on the context menu. Check that the Library option button is selected. Press the space bar and notice how the highlight moves to the next member in the numbering sequence. Select the Structure > Attributes > Material Properties command. TUTORIAL 2 – STEP 14 Step 15 – Analyse. Click the Display Results Values button on the Display toolbar and the bending moment diagram will be labelled with bending moment values. Click on the Display Load Values button on the Display toolbar and notice the arrow is now labelled with the value of the load. Notice the whole structure is highlighted indicating that all members have a material number of "1". Click the All button and the OK button in the load case selection dialog box. Step 16 – Display results. press Enter. The bending moment diagram should now be displayed. Close the analysis program window by clicking on the X button when the analysis is completed. type "-5" in the F1 = edit box. click on OK. check that the Type combo box is set to FY and that the Local option button is selected. select the Loads > Node Loads command. Microstran V9 12:Input Tutorials • 231 . Select the Loads > Add Case command. click on the top left node. Select the Query > Member Forces command. Step 14 – Input loads. Select the Analyse > Linear command. right-click to terminate the command. click on OK. This may be scrolled if the results you want are not shown.Step 13 – Input material from library. double-click on STEEL. type "10" in the X edit box. Notice the arrow indicating a node load. type "Wind load". click on Accept. Select the Loads > Member Loads command. Click on the Bending Moment Mz button on the Results toolbar. click on the Uniform button.
and the apex height is 5 m. click on OK or press Enter. Step 2 – Set the job name. Initially. titles etc. Step 1 – Start Microstran. click on the Save button in the dialog box. The side dimension is 20 m. Check that the Space frame and Y axis option buttons are selected. Select m. Type a job title and press Enter. t. select the File > Exit command. Click on the Save Job button (the one with the diskette). Select New on the File menu or click on the New Job button. and then the rafter and column are reflected about a plane parallel to the YZ plane. °C for units if not already selected. 232 • 12:Input Tutorials Microstran V9 . click on OK. the method adopted is to input a quarter of the structure. There are many different ways of creating a model such as this and this tutorial illustrates a few interesting techniques. Tutorial 3 – A 3-D Example TUTORIAL 3 – A 3-D EXAMPLE In this tutorial we input the structure and loads shown in the above diagram. Maximize the Microstran window if it is too small. the column is then moved 10 m in the +Z direction. ABCDE. and then to perform a polar copy about the vertical axis. type "TUT3" for the job name (do not include the quotes). AB. click on OK.Step 18 – Save Job and exit Microstran. and the rafter. the column. click OK to accept the default job file folder. BC. are drawn in the XY plane. With reference to the diagram. select Programs and then Microstran. kN. Click on the Windows Start button. the eaves height is 3 m.
click on the vertical member. click on both members. check that X is selected for the normal axis. Notice that the Node Coordinates dialog box has appeared and now displays your keystrokes. in the Reflect dialog box. and C. move the mouse to draw a vertical member 3 m high and then click. A. Click on the Snap to Grid button on the Draw toolbar at the right of the main window. Step 5 – Reflect column and rafter. right-click and select OK on the context menu. Step 4 – Move column to corner. A. type "0 0 10" and press Enter. fall conveniently on grid points (using the Structure > Drawing Settings > Grid Spacing command. Click on the Reflect button on the Draw toolbar. Click on the Draw Members button. Microstran V9 12:Input Tutorials • 233 .Step 3 – Draw column and rafter in XY plane. click on the Front View button on the View toolbar at the top of the window. right-click and select OK on the context menu. Click the right mouse button and on the context menu select End Line.2". the grid spacing may be set in each direction to values other than 1 m). You may draw a member to a point which is not on the grid either by entering the coordinates or relative coordinates of the point instead of attempting to click on it. click the mouse on any grid point at the lower left of the screen. Notice now that the prompt area of the status bar displays a message "Click on point or enter offset". Right-click to terminate the command. type "R10. or by clicking on a nearby grid point and subsequently moving the node so created. Click the Move Members button on the Draw toolbar. click the right mouse button to terminate the command. B. Click on the right end of the rafter. the nodes. TUTORIAL 3 – STEP 3 Note: In this example. and click on the OK button. Press Enter and notice that a rafter has been drawn to the point 10 m to the right and 2 m up from the top of the column. select Extrude nodes.
position the cross-hair cursor near the middle of the lower horizontal member and click. The view has now changed to the default oblique view for a 3-D structure. de-select it by clicking on it again. Notice that the grid now disappears. If you accidentally select the wrong member. Notice the appearance of small square symbols at each node. right-click to terminate the command. Click on the Erase Members button on the Draw toolbar and click on each of the four baseline members. Click on the Display Node Symbols button on the Display menu. Note that you can also select members by enclosing them in a selection box created by clicking on a corner and dragging to the diagonally opposite corner. Click on the Snap to Mid/End button on the Draw toolbar. Step 8 – Draw interior columns.Step 6 – Change viewpoint. Right-click and select OK on the context menu. Now. TUTORIAL 3 – STEP 8 Step 9 – Erase baseline members. click on the mid-point of the upper horizontal member. Click on the Draw Members button. Right-click and select Break Line on the context menu. Right-click and select End Line on the context menu. TUTORIAL 3 – STEP 6 Step 7 – Select middle/end snap mode. 234 • 12:Input Tutorials Microstran V9 . Click on the Oblique View button on the View toolbar. The horizontal members have been sub-divided automatically by drawing the column at the mid-points. notice that the beginning of a new member snaps to the mid-point of the member. draw columns at the quarter-points by repeating this procedure.
Click on the Draw Members button. right-click and select Break Line. Click on the Sub-divide Members button on the Draw toolbar. Click on the top of the central column. draw beam and central rafter. click on the lower third-point of the right upper rafter. Click on the Draw Members button. click on the top of the left interior column and then the mid-point of the left rafter. right-click and select Break Line. click on the mid-point of the upper beam. right-click to terminate the command. click on the top parts of the left and right rafters. Repeat for the right rafter but select End Line. TUTORIAL 3 – STEP 11 Microstran V9 12:Input Tutorials • 235 . right-click and select OK. click on the up spin button so that the number of segments is "3". TUTORIAL 3 – STEP 10 Step 11 – Sub-divide upper rafters. click on the OK button. right-click and select End Line. click on the lower third-point of the left upper rafter.TUTORIAL 3 – STEP 9 Step 10 – Draw outer rafters.
right-click and select OK. select "3" for the section number and click on OK. Notice the prompt to "Click on centre of rotation or enter coordinates". 236 • 12:Input Tutorials Microstran V9 . right-click and select OK. Click at the bottom right of the structure and drag to the top left. click on each of the five support nodes. Click on the Zoom Extents/Limits button on the View menu to redraw the structure filling the display. It is not essential that the upper third-point nodes are eliminated. Instead of sub-dividing. enclosing the whole structure with the selection box. Click on the Input Supports button on the Attributes toolbar. Select the View > Redraw command. Rightclick to terminate the command. Step 14 – Input section numbers. click on the pinned support button and then the OK button. Click on the apex node. Step 13 – Input supports. click on all parts of the left and right diagonal rafters. moving the extra node to one end has stretched one part of the member to the full length and made the other part a zero-length member. click on the Display Supports button on the Display menu. Notice that the extra nodes have now gone. type "90" for Angle and "3" for Number of copies. Step 15 – Perform polar copy. right-click and select OK. Select the Structure > Move > Node. which is automatically eliminated. Press Enter. Notice the symbols at each support.) Note: The upper part of each rafter was sub-divided into thirds as a convenient means of locating the node at which the upper beam is connected to the rafter. Click on the Member Numbers button to turn on member numbering and the Display Supports button to turn off support display. right-click. right-click to terminate the command. right-click and select OK. In the Polar Copy dialog box. click on the OK button. Select the Structure > Copy > Polar command. select Y for Axis of rotation. (In each case. Notice the new section numbers on the rafters and beams. click on the apex node. click on the upper spin button and select "2". click on the top third-point node on the left upper rafter. right-click. and the new colours. a single node could have been introduced into each upper rafter by use of the Structure > Insert Node command. Repeat this operation for the extra node on the right upper rafter.Step 12 – Eliminate extra nodes in upper rafters. Click on the Input Section Number button on the Attributes toolbar. Click on the other rafters and beams.
you could readily use both X and -X and Z and -Z as reference axes for columns not on the corners. We require that corner columns are rotated 45° and that other front and rear columns be rotated 90°. type "Z" and press Enter. Click on the Zoom Extents/Limits button to redraw the view. the apex node will be used as a "reference node" (see "Member Definition" on page 83). select a 250 mm UB section. Click the Input Reference Node/Axis button on the Attributes toolbar. Note: The y axes of all columns point to the left (-X) while the y axes of all roof members point up (+Y). Step 17 – Input sections from library. To achieve this. double-click on STEEL. click on OK. Click the button again to turn off rendering. These are default orientations. Notice the prompt "Select reference node or enter node/axis". Select the Structure > Attributes > Material Properties command. right-click to terminate the command. Click on the Input Section Properties button. click on OK in the Reference Node/Axis dialog box. check the Member axes box. click on OK for section 1. right-click and select OK. click on OK. When setting the orientation of the corner columns. click the Members tab. Step 18 – Input material from library.TUTORIAL 3 – STEP 15 Step 16 – Set orientation of columns. click on OK. Click on each of the other front and rear columns. Note: There are some advantages in steel design in having the simple convention for column orientation that all column y axes point outwards. click on each of the corner columns. Check that the Library option button is selected. Select the View > Display Options command. Click on the Render button on the Display toolbar and notice the section shapes have been displayed. Repeat the process. click on OK. click on UB. right-click and select OK. Notice that the columns are now oriented as required. uncheck the Member numbers box. uncheck Member axes box. Microstran V9 12:Input Tutorials • 237 . Section 1 has now been input. Notice the whole structure is highlighted indicating that all members have a material number of "1". selecting a 200 mm UB for section 2 and a 300 mm UB for section 3. click on OK. Click on the apex node. click the Members tab. Select the View > Display Options command. Click on the OK button in the Material dialog box.
238 • 12:Input Tutorials Microstran V9 . Click the All button and the OK button in the load case selection dialog box. TUTORIAL 3 – STEP 19 Step 20 – Analyse.Step 19 – Input loads. Step 21 – Display results. click on OK. Select the Loads > Add Case command. type "-5" in the F1 = edit box. Select the Analyse > Linear command. select another box enclosing just the upper beams. Notice that all rafters have now been selected. select the View > Limit > Boundary command. Select the Loads > Member Loads command. Click the Display Results Values button on the Display toolbar and the bending moment diagram will be labelled with bending moment values. click at the left of the view and drag to the top right. The last point should be clicked near the first point to close the boundary. select another box that encloses just the eaves beams. click on the Front View button. type "Design case". click on Accept. Click on the Plan View button. Right-click to terminate the command. click on the Uniform button. The bending moment diagram should now be displayed. Click on the Oblique View button. check that the Type combo box is set to FY and that the Global option button is selected. starting at the bottom left. enclosing all roof members. click the corners of a narrow rectangle enclosing the diagonal rafter. Right-click and select OK. Click on the Bending Moment Mz button on the Results toolbar. TUTORIAL 3 – STEP 21 Step 22 – Display results for diagonal rafter. Close the analysis program window by clicking on the X button when the analysis is completed.
The connections between beams and rafters would usually be such that this moment transfer does not occur. select the File > Exit command. You may insert moment releases in the beams to more accurately model this situation. These are caused by bending moments transferred from the beams. TUTORIAL 3 – STEP 22b Note: The discontinuities in the bending moment diagram at the points where the beams meet the diagonal rafters. Notice that the bending moment diagram displayed is now a view at right angles to the diagonal rafter. click on the Save button in the dialog box.TUTORIAL 3 – STEP 22a Click on the Front View button and a few times on the Viewpoint Left button to rotate the axes so that the X and Z axes are coincident. Microstran V9 12:Input Tutorials • 239 . Step 23 – Save Job and exit Microstran. Click on the Save Job button (the one with the diskette).
240 • 12:Input Tutorials Microstran V9 .
These functions are selected with the File > Import > CAD DXF command and the File > Export > CAD DXF command. Conversely. Note: You can use the Windows Paste command to transfer any part of a Microstran image into CAD. In some situations. Structure information is exchanged by means of an AutoCAD DXF. Microstran's RC Detailing option creates a DXF to transfer RC details to CAD (for more information. an architect's drawing files may be used for this purpose. see Chapter 19 – "RC Design & Detailing". Microstran V9 13:CAD Interface • 241 . Microstran is compatible with the AutoCAD Release 12 DXF format. In other situations. You can easily create a Microstran model by importing a suitable CAD DXF. it may be expedient to have a drawing prepared in CAD so you can import the structure directly into Microstran. when you have a Microstran model.13:CAD Interface General The CAD Interface is an integral part of Microstran offering the capability of exchanging 3-D data between a structural model and CAD systems. it's possible to export a DXF that could become the basis for a CAD drawing.
A line may represent more than one member. Members are numbered in the order in which they are present in the DXF. or that the ends of other members lie on it and will sub-divide it automatically into the series of members required for analysis. For example. On selecting the File > Import > CAD DXF command a file selection dialog box is displayed so you can browse for the DXF file that you wish to import. where the chord of a truss is represented in the drawing as a single line. Microstran will detect that other members intersect with it.Importing a CAD DXF Members must be represented on the drawing as straight lines (using the AutoCAD "LINE" entity). the factor would be 0. The dialog box below is then displayed. the drawing is in mm and the Microstran model is to be in meters. Nodes are numbered in order of increasing vertical axis coordinate. Nodes separated by less than this distance will be treated as coincident. Factor A coordinate conversion factor – the multiplication factor to be applied to drawing coordinates to produce coordinates used in the analysis. for example. SELECT DXF LAYERS Layers All layers in the DXF are shown in the list box and you can select any that contain lines to be imported.001. Microstran assigns each specified layer a number and every member found on that layer is assigned a section number equal to the layer number. If. Tolerance The minimum node separation. Nodes are not represented separately in the DXF but are obtained from the coordinates of the ends of the lines. Only lines in the specified layers will be imported. All members from a sub-divided line are grouped together. 242 • 13:CAD Interface Microstran V9 .
After reading the file into AutoCAD with the "DXFIN" command.Exporting a CAD DXF Member centre-lines are represented by a single line in the DXF. On selecting the File > Export > CAD DXF command the dialog box below is displayed. If section properties have been extracted from a steel section library the section shape may also be represented by a number of planes. In programs such as AutoCAD. you may use the "ZOOM E" command to fill the screen with the drawing. Windows Clipboard Operations Microstran facilitates use of the Windows clipboard for transfer of images to CAD programs by using the Enhanced Metafile Format (EMF) for the Windows clipboard when you select the View > Copy command. Pressing the Print Screen key on the keyboard writes a Windows bitmap to the clipboard. The limits may then be adjusted as required. The section shapes may be curtailed at member ends to avoid overplotting at the intersections. Both of these formats may be pasted into Microsoft Word documents. you can use the Paste command to directly insert an image of the main Microstran view. You may suppress hidden lines and render the drawing using AutoCAD. CAD DXF EXPORT PARAMETERS Do not check the box for detailing output unless you are using a Microstran-compatible detailing interface. The DXF contains only an Entities section without a drawing header. Microstran V9 13:CAD Interface • 243 .
244 • 13:CAD Interface Microstran V9 .
which enables you to take into account the non-linear actions arising from the displacement of loads (the P-∆ effect). is solved separately because superposition of results is not valid. Linear Elastic Analysis is a first-order elastic static analysis in which non-linear effects are ignored and the stiffness equations are solved for only the primary load cases. λc is used in steel design codes for the computation of moment amplification factors. for selected load cases and computes the corresponding member effective lengths for each load case. The Master-Slave Constraints option is available with all types of analysis and is particularly useful for the modelling of elements that are effectively rigid in their own plane. Members defined as tension-only. Dynamic Analysis computes the natural vibration frequencies of the structure and the associated mode shapes. The dynamic loads on the structure due to earthquake or other support acceleration may then be assessed using the response spectrum method. each of which employs exhaustive consistency checking and highly efficient equation solution procedures. The Profile Optimizer is used in all analyses to minimize analysis time and storage requirements. Non-Linear Analysis is a second-order elastic analysis. or brittle fuse are checked at each iteration and included or excluded according to their respective constitutive rules.14:Analysis General Microstran offers a number of static and dynamic analysis options. Nodes and members can be numbered for maximum convenience in data generation and interpretation of results. such as floor slabs. and the shortening of members subjected to bending (the flexural shortening effect). Nonlinear analysis is an iterative procedure in which the behaviour at each step is controlled by a number of parameters. compression-only. gap. Solutions for combination load cases are obtained by superposition of the solutions for the primary load cases. the change in flexural stiffness of members subjected to axial forces (the P-δ effect). Each selected case. whether a primary or combination load case. λc. Elastic Critical Load Analysis calculates the frame buckling load factor. Microstran V9 14:Analysis • 245 .
is assembled from the stiffness contributions of individual members. P.Method Microstran uses the well-documented direct stiffness method of analysis in which the global stiffness matrix. A "well-conditioned" structural model is one in which the condition number is less than about 104. which can be listed and printed using options on the File menu. Data errors and warnings are shown in the output window and are also written to the error report. is calculated after the decomposition of the [K] matrix. Load vectors. complex structural models. For example. See "Report Contents". the large displacement of a node or group of nodes may indicate that the structure or part of it is acting as a mechanism. u. At unrestrained nodes the sum of all the member end actions is compared to the sum of external forces 246 • 14:Analysis Microstran V9 . are determined by solving the equation: P = [K] u The forces in each member are then determined by multiplying the member stiffness matrix by the appropriate terms of the displacement vector. For Non-linear analysis the condition number is computed only after the first analysis iteration and may not give a meaningful measure of the final analysis result. [K] can be quite large and is stored on disk in blocks sized to maximize the use of available memory and to minimize solution time. [K]. If displacement control is actuated the condition number reflects the transient stabilization of the model and is unreliable. If the condition number exceeds this value you should treat the results with caution and look for evidence of "ill-conditioning". The consistency check will detect a range of modelling problems related to geometry and loading. For large structures. Residuals An important independent check on the accuracy of the solution is provided by the node equilibrium check. resolved into member axes. Accuracy All analyses use double-precision arithmetic to minimize the loss of precision inherent in the many arithmetic operations required for solving large. Condition Number The condition number. Consistency Check Microstran performs an automatic check of all input data prior to analysis. a measure of the loss of precision that has occurred during solution. are formed from the applied loads and node displacements. Microstran analysis modules report the condition number (CN) and maximum residuals to assist in interpretation of the analysis results.
There is no single method of iterative non-linear analysis for which convergence is guaranteed. Results for combination load cases are determined by superposition of the results of the component primary load cases. Non-Linear Analysis Non-Linear Analysis (also called second-order analysis) performs an elastic analysis in which second-order effects may be considered. gap. Note: If you perform a non-linear analysis and then a linear analysis. The maximum residual is reported in the Analysis window. Non-linear analysis uses a multi-step procedure that commences with a linear elastic analysis. This may be the case as the elastic critical load is approached. the out-of-balance force. The solution may not converge if the structure is subject to gross deformation or if it is highly non-linear. Performing a linear analysis sets the analysis type flag to L (linear). or fuse). An error message will be displayed if you attempt linear analysis of a model containing non-linear members. The maximum residual should be considered in conjunction with the magnitudes of the applied loads in assessing the adequacy of the solution. Any difference is a force residual. See "Instability & Ill-Conditioning" on page 72. Note: You should not attempt to use non-linear analysis to determine elastic critical loads. Further corrections are computed until convergence occurs. The load residuals. Microstran V9 14:Analysis • 247 . computed for the structure in its displaced position and with the stiffness of members modified. by itself. is not sufficient to ensure an accurate solution – the condition number must also be satisfactory.acting on the node. are applied as a new load vector to compute corrections to the initial solution. It may therefore be necessary to adjust the analysis control parameters in order to obtain a satisfactory solution. The different second-order effects are described below. cable. compression-only. the settings in the Select Analysis Type dialog box will be lost (see "Selecting Load Cases for Non-Linear Analysis" on page 251). Results of non-linear analysis should be treated with caution whenever the loading is close to the elastic critical load. Note: A satisfactory equilibrium check. Linear Elastic Analysis Linear elastic analysis cannot be performed if there are any non-linear members in the model (tension-only. All load cases are analysed when you choose linear analysis.
These are discussed in detail below. Full account is taken of the effects of axial force on member flexural stiffness while the effects of node displacement are approximated by a sidesway correction in the stability function formulation. which provides the most rigorous solution for all structure types. This is the default analysis type. Node Coordinate Update * NO Axial Force Effects NO Analysis Type Linear elastic analysis with tension-only or compression-only members taken into account. These settings normally give minimum solution time with second-order effects taken into account. YES NO NO YES YES YES * Node coordinate update is automatically enabled for models containing cables.Second-Order Effects The most important second-order effects taken into account in non-linear analysis are the P-Delta effect (P-∆) and the P-delta effect (P-δ). P-∆ AND P-δ EFFECTS You may independently include or exclude these two major effects. 248 • 14:Analysis Microstran V9 . Analysis includes the effects of displacement due to sidesway but not changes in member flexural stiffness due to axial force. These settings will usually yield satisfactory results for pin-jointed structures. Different combinations of the P-∆ and P-δ settings affect the operation of non-linear analysis as set out in the table below.
Either small displacement theory or finite displacement theory may be used with node coordinate update. This is called the P-delta effect (P-δ) and is taken into account by adding beam-column stability functions to the flexural terms of the member stiffness matrices.Node Coordinate Update – P-Delta Effect The P-Delta effect (P-∆) occurs when deflections result in displacement of loads. P-∆ is taken into account either by adding displacement components to node coordinates during analysis or by adding sidesway terms to the stability functions used to modify the flexural terms in the member stiffness matrices. SMALL AND FINITE DISPLACEMENT THEORIES Axial Force Effects – P-delta Effect The bending stiffness of a member is reduced by axial compression and increased by axial tension. Member stiffness matrices therefore vary with the axial load and are recomputed at every analysis iteration. As shown in the diagram below. causing additional bending moments that are not computed in linear analysis. finite displacement theory takes into account the rotation of the chord of the displaced member in computing the end rotations and the extension of the member. Only where large displacements occur would the use of finite displacement theory produce results different from those obtained with small displacement theory. The stability functions are derived from the "exact" solution of the differential equation describing the behaviour of a beamcolumn. Microstran V9 14:Analysis • 249 . The additional moments caused by P-δ are approximated in some design codes by the use of moment magnification factors applied to the results of a linear elastic analysis.
compression-only. is shown in the diagram below. At the conclusion of each analysis step. If the member is also subjected to axial load.Flexural Shortening As a member flexes under the action of bending moments its chord shortens. FLEXURAL SHORTENING Changes in Fixed-End Actions Member fixed-end actions may change between successive analysis iterations owing to displacement of the member and variations in its flexural stiffness caused by axial force. no solution is possible. the flexural shortening is increased by compression and decreased by tension. all tension-only. This effect. known as the flexural shortening effect or the bowing effect. Microstran automatically recalculates the fixed-end actions at each analysis iteration and updates the load vector accordingly. Some formulations for flexural shortening consider only the effects of end moments but Microstran also takes account of any loads applied along the member. irrespective of whether second-order effects are to be considered. If the removal of non-linear members causes the structure to become unstable. giving rise to an apparent decrease in axial stiffness. gap or fuse members are checked and may be removed from or restored to the model for the next analysis step depending on the relative displacement of end nodes. 250 • 14:Analysis Microstran V9 . Non-Linear Members Analysis of models containing non-linear members requires non-linear analysis.
Microstran V9 14:Analysis • 251 . the analysis type flag (S/L/N) will be unconditionally set to Linear. only "realistic" load cases should be selected for non-linear analysis – there is no point in analysing a wind load case. In this case. A load vector is formed for each load case to be solved. where linear analysis may be adequate. whether it is a primary load case or a combination load case. On selecting the Analyse > Non-Linear command the dialog box shown below is displayed. In the Type column. or is to be ignored (Skipped). where non-linear analysis may be required. There is no need to analyse any load cases for which results are not required. The latter capability may be useful when results are required for load cases representing serviceability. SELECTING LOAD CASES FOR NON-LINEAR ANALYSIS In general. because this load will never exist in isolation. It is also necessary when the model includes members to be designed to codes with different analysis requirements.Running a Non-Linear Analysis Selecting Load Cases for Non-Linear Analysis Non-linear analysis lets you specify the load cases to be analysed and the analysis type to be used for each load case. load cases are identified as Primary or Combination. The linear setting allows you to perform linear analysis on models with non-linear members and to obtain results for both linear and non-linear analysis in a single pass. You must reinstate the analysis type flag if you revert to non-linear analysis. This is particularly important for structures containing cable elements because analysis may not be possible unless self-weight is included. and for ultimate strength. Note: The settings in this dialog box will be lost if you subsequently perform a linear analysis. for example. The second character is a code that specifies whether the load case is to be processed with Linear analysis or Nonlinear analysis.
NON-LINEAR ANALYSIS PARAMETERS The dialog box contains the following items: • Node coordinate update (P-∆) This flag is set if node coordinates are to be updated at each analysis step. The default setting is off. Axial force effects (P-δ) If this flag is set member stiffnesses are modified at each analysis step. Residual uses a function of the maximum out-of-balance force after analysis. When Displacement is selected convergence is determined by comparing the convergence tolerance against a generalized measure of the change in displacement between successive iterations. either small or finite displacement theory must be selected. You should usually leave this control at minimum and only increase the setting if difficulties Microstran V9 • • • • • 252 • 14:Analysis . The default setting is on. Set this flag to take into account the variation in member axial stiffness caused by the shortening of members subjected to flexure. Small displacement theory is the default setting. Residual / displacement Specifies the criterion to be used for convergence of the analysis. For a satisfactory solution there must be acceptably small changes in the displacement and the residual must be small. Small/finite displacement theory If the node coordinate update flag has been set. It is automatically set for structures containing cable elements. Flexural shortening This flag may be set only if the axial force effects flag is set. The default setting is Residual.Non-Linear Analysis Parameters The dialog box shown below determines the characteristics of the nonlinear analysis. Displacement control Increasing the setting of this control may assist convergence in situations where displacements appear to diverge with successive analysis iterations. The default setting is on. or for structures that are initially unstable but become stable as they displace under load.
0005. The default setting is off.are encountered in solution. Settings above minimum affect the calculation of the condition number. displacements increase disproportionately with load) have an optimum relaxation factor between 1. Caution is recommended in changing the relaxation factor from the default value of 1.0 and 1. Instability Instability detected during linear analysis is usually due to modelling problems and some of the common causes of these are discussed elsewhere. This parameter is used to stop the analysis if convergence is taking an excessive time. structures which "soften" under load (i. Microstran V9 14:Analysis • 253 . Iterations per load step The maximum number of analysis iterations for each load step. determined by checking the change in the convergence criterion between successive analysis cycles.85. but larger values may be required for very flexible structures or those containing large numbers of cable elements.2 while structures which "harden" under load have an optimum relaxation factor as low as 0. This parameter is usually left at its default value of 1. Note that at this stage. load steps You may apply loads in a stepwise fashion which may assist in obtaining a solution for flexible structures by keeping displacements small at each load increment. i. • Convergence tolerance This value determines when the analysis has converged. the values shown are for the most critical degree of freedom. and displacements may be either translations or rotations.e. Too small a value will prolong the solution time and may even inhibit convergence. • • • • As the analysis proceeds.. The default value is 0.. As a general rule. residuals may be either forces or moments.0.e. The optimum value for the relaxation factor depends on the type of the structure. No. Relaxation factor The relaxation factor is applied to incremental displacement corrections during analysis. The default value is 50. At each analysis iteration the maximum values of residual and displacement are displayed. the analysis window displays key information for each selected load case. Oscillation control This control facilitates convergence when the solution oscillates owing to the removal and restoration of tension-only or compression-only members. if the relaxation factor is too far from optimum the analysis may require an excessive number of iterations for convergence or it may not converge at all.
a successful analysis may result if either node coordinate update or axial force effects are excluded. In other cases. This may occur. Perform an elastic critical load analysis to check the frame buckling load. set the analysis type to L for these load cases. perhaps. Examine the static analysis log file. non-linear analysis may detect buckling of individual members or of the whole frame. If an unstable member is detected during the update process at the end of each iteration. Troubleshooting Non-Linear Analysis It is possible to perform a successful linear analysis for structures that are incapable of resisting the imposed loads. When non-linear analysis fails to converge. • • • 254 • 14:Analysis Microstran V9 . An elastic critical load analysis will often assist in locating the cause of local instabilities. The results of an analysis in which instability has been reported are useful for diagnosis but should not be used for other purposes. However.Because a non-linear analysis considers the effects of axial force on member stiffness it is able to detect a range of instability that linear analysis cannot. If not. the presence of the instability will be reported in the Analysis window and some diagnostic information will be written to the static log file to assist you in correcting the problem. Is a full non-linear analysis necessary? If the only significant nonlinear effect is the presence of tension-only or compression-only members. the following tips may be helpful: • Make sure that a linear analysis can be performed. troubleshoot the linear analysis before continuing with the nonlinear analysis.g. if some compression members are slender and buckle. if the instability is not in a single member but localized in a small group of members it may not be detected until the completion of the analysis. In this case. The manner in which a structure is modelled and the analysis parameters used can have some bearing on the stage of the analysis when instability of individual members is detected and the way in which it is subsequently treated. change to tension-only members. For example. results are available and may be used to determine corrective measures. increase some member sizes or. Non-linear analysis is a more complete simulation of the behaviour of a structure under load and the procedure may fail to provide a solution where a linear analysis succeeds. it will be deleted from the following iteration. If it is less than the imposed load non-linear analysis is not possible. for example. The presence of unstable members is reported in the Analysis window and details are written to the static log file. e. It contains information about members that have buckled or become ineffective. Even though the analysis has failed.
reasonable estimate of the collapse load of a rigid-jointed structure (Livesley). at which the displaced position of the structure is maintained without any additional load and the equilibrium configuration of the frame is not unique.0 for any load case indicates that the structure is unstable under the applied loading. the frame must be modelled as a space frame with the appropriate out-of-plane restraints. The elastic critical load of a structure is essentially a generalization of the Euler buckling load of a pin-ended strut. The mode shape indicates whether buckling involves the frame as a whole or just localized buckling of one or more frame members. if out-of-plane buckling behaviour is to be considered for a plane frame. Note: Lateral torsional buckling (also called flexural-torsional buckling) is not taken into account in ECL analysis. Adjust non-linear analysis parameters. Effective length factors. The elastic critical load provides a practical. which is the factor by which the initial axial forces in the frame must be multiplied to cause the structure to become unstable. only the first buckling mode is required but higher modes will be of interest if lower modes represent localized buckling behaviour or they are inhibited by constraints not in the model. Microstran V9 14:Analysis • 255 . Sometimes. The initial axial forces in a frame are obtained from a static analysis. The effective length of a compression member is the length of an equivalent pin-ended member whose Euler load equals the axial force in the member when the frame buckles. it is helpful to remove ALL releases and reinstate them in stages. Buckling mode shapes can be displayed for each load case. For example. which are multiplying factors (k) applied to the actual member length. The elastic critical load of the structure is a function of the elastic properties of the structure and the applied loading. are calculated for both member principal axes for each load case. Member effective lengths are determined. • Elastic Critical Load Analysis Elastic Critical Load (ECL) Analysis performs a rational buckling analysis to compute elastic critical loads for the frame and the associated buckling mode shapes. A load factor of less than 1. Normally. A linear elastic analysis is usually sufficient but non-linear analysis must be used when the structure contains non-linear members. in diagnosing convergence problems.• Is the structure too flexible? Remove excessive member end releases (pins). Restraints affecting the flexural buckling behaviour of the structure must be included in the structural model. The elastic critical load is computed separately for each load case and is reported as a buckling load factor (λc).
Selecting Load Cases for ECL Analysis Select the Analyse > Elastic Critical Load command. • 256 • 14:Analysis Microstran V9 . SELECTING LOAD CASES FOR ECL ANALYSIS Analysis Control Parameters The settings in this dialog box determine the type of elastic critical load analysis that will be performed. Too small a value will prolong the solution time. The default value is 0.01. The dialog box below is displayed for you to select the required load cases.Elastic critical load analysis is not recommended for structures containing cable elements because of the highly non-linear nature of structures of this type. It is normally Linear but must be Non-linear if the structure contains non-linear members. Tolerance The tolerance is the relative accuracy to which load factors are required. ECL ANALYSIS PARAMETERS The dialog box contains the following items: • Initial analysis Sets the initial analysis type to determine the distribution of axial forces used for the elastic critical load analysis. Usually you would select only combination load cases for design.
• Max. The default value is 1000. Microstran V9 14:Analysis • 257 . load factor The search for the elastic critical load will terminate if the load factor exceeds this limiting value. modes The number of buckling modes to be computed for each selected load case. • When the analysis is finished a summary of results appears in the analysis window. No. Higher modes will be of interest if lower modes represent localized buckling behaviour. The summary shows for each selected load case the critical load factor and the most critical member with associated k values. Normally. only the first mode is required.
The unit used for mass must be consistent with the force and length units.Dynamic Analysis Dynamic Analysis computes the frequencies and mode shapes of the natural vibration modes of the structural model. Freq. the dialog box shown below appears. The settings in this dialog box determine the type of dynamic analysis that will be performed. Analysis Control Parameters After selecting load cases. shift Modes will be found above this frequency value (Hz). Select the Analyse > Dynamic command to start dynamic analysis. Member masses are computed automatically as the product of the cross-sectional area and the mass density. modes The number of natural frequencies and mode shapes that can be computed is limited by the number of dynamic degrees of freedom. The frame mass is computed automatically and additional mass that is to be taken into account may be modelled as node masses. No. • • • 258 • 14:Analysis Microstran V9 . Band of Modes In this method only modes lying between the from and to values will be computed (Hz). and. Solving for a large number of modes is usually not warranted. DYNAMIC ANALYSIS PARAMETERS The dialog box contains the following items: • Sequence of modes This is the default method – modes will be computed from the lowest frequency. by the amount of available memory. for large structures. Static load cases are ignored. Additional node masses may be input as required. Only the mass and stiffness of the model are considered in computing natural frequencies and mode shapes.
The default value is zero.00001. the eigenvalues found may not be the lowest. Verify eigenvalues Check this box if you wish to verify that no eigenvalues have been skipped in the computation (see above). For example. Tolerance This is the tolerance to be used in determining the convergence of eigenvalues. The default value is 0. If the value is too large. Freq. including torsional modes. to Modes with a frequency greater than this value (Hz) will not be found. • • • • • • • Dynamic Modes After completing a dynamic analysis it is important to check the mode shapes to ensure that you have the required dynamic modes. Response spectrum analysis You must check this box if you wish to proceed to a response spectrum analysis after the dynamic analysis. Frequency list Modes with a frequency between the first and last values (Hz) will be found. Distribution of modes Use this method to count the number of modes whose frequencies are lower than the specified values (Hz). from Modes with a frequency less than this value (Hz) will not be found. Microstran computes all dynamic modes. Microstran V9 14:Analysis • 259 . Lumped mass / Consistent mass The mass matrix may be computed using either a consistent mass or lumped mass formulation. which leads to a diagonal global mass matrix Initial state load case Non-linear behaviour is not taken into account in dynamic analysis but it is possible to specify a load case that defines the initial state. Mode shape results are not produced. The consistent mass matrix has a firmer theoretical basis but gives rise to a global mass matrix that is similar in shape and size to the global stiffness matrix. the slack cable will be eliminated from the analysis.• • Freq. If the value is too small. requiring greater storage and computational effort than the lumped mass matrix. a leeward cable in a guyed mast subjected to wind load may be slack. If the corresponding load case is specified as the initial state load case. convergence may not be possible or an excessive number of iterations may be required. The easiest way to examine the results is to display an animated view of the computed mode shapes.
3 bays x 2 bays x 4 storeys. Dynamic Analysis Example Example EX6 is a rectangular building frame. Running a Response Spectrum Analysis The procedure for performing a response spectrum analysis is: 1. which was generated with Standard Structures Input. Dynamic analysis shows the first two modes are sidesway modes and the third is a torsional mode.Note: You can add low-mass "semaphore" members to visualize torsional modes. Set up static analysis load cases using the dialog box shown below and perform the static analysis. 260 • 14:Analysis Microstran V9 . The earthquake load cases are empty – results from the response spectrum analysis will be added automatically. Additional mass of 10 tonnes is attached at each unrestrained node. NATURAL MODE SHAPE Response Spectrum Analysis Response Spectrum Analysis is used to determine peak displacements and member forces due to support accelerations. The mode shape associated with the third mode is shown below.
For each earthquake load case you must enter parameters to determine the response spectrum direction and the number of modes to be considered. 4. Microstran V9 14:Analysis • 261 . Select dynamic analysis and check item Response spectrum analysis. The Delete button removes all dynamic analysis data associated with the load case. You are next prompted to identify the load cases that are to be used for the results of the response spectrum analysis. above). It must not be greater than the number of modes computed during dynamic analysis (2. The direction factors determine the direction of the support acceleration in terms of components in the global axis directions. 3. These components will be reduced to a unit vector before being used. There will be one such load case for each earthquake direction being considered.2. The number of modes must be sufficient to satisfy the earthquake code requirement that 90% (typically) of the seismic mass is accounted for.
For each earthquake load case damping ratios are specified. For each earthquake load case a response spectrum curve and scaling factor must be specified. The spreadsheets referred to above will assist you in computing scale factors to comply with code requirements.5. This is equivalent to the "Square Root of the Sum of Squares" (SRSS) method if all modal damping ratios are zero. The response spectrum curve is chosen from a list of names of digitized response spectrum curves contained in file Response. The "Complete Quadratic Combination" method (CQC) for combining modal responses is used to determine the peak response. The total reactions (base shears) are displayed for each earthquake case and you now enter scale factors for each case. select the Analyse > Response Spectrum command to scale the computed actions and combine them with the static analysis results (note that this item is greyed out on the menu until all the necessary preconditions for response spectrum analysis have been completed). 6. You may edit the response spectrum curves or add new ones using the Configure > Edit Response Spectra command. the dynamic analysis proceeds. After steps 3-6 have been completed for each earthquake case. 262 • 14:Analysis Microstran V9 . 7.txt (described below). On completion.
The diagram below shows the displaced shape for one of the earthquake load cases. There are no negative values. Interpretation of the results should take this into account. Earthquake load cases may now be treated as any other load case for the display and reporting of results and for design.Microstran now adds the results from the response spectrum analysis to the static analysis results. Microstran V9 14:Analysis • 263 . DISPLACED SHAPE FOR EARTHQUAKE LOAD CASE Note: The displaced shape represents the peak values of the displacement during the earthquake event.
5. Any combination case that refers to the dynamic case is updated by adding the specified dynamic case.xls set out detailed procedures for performing response spectrum analysis complying with the design codes AS 1170. respectively. 264 • 14:Analysis Microstran V9 . file Response. For convenience. Note that the values given for the reactions are the sum of absolute values. factored as specified. any nonlinearity in the previously computed results is preserved. the static analysis must be repeated if the dynamic analysis is to be amended. which contains important data including mass participation factors. Note: After running response spectrum analysis you should look at the dynamic analysis log file. as the methods used to combine individual modal responses result in loss of sign. As this process takes place. The results of the static analysis are updated with the results of the response spectrum analysis. The factor should be based on the base shear in the direction of the support acceleration.txt uses normalized spectral values.xls and Nzs1170_5. The results for each dynamic load case are inserted in the results files for the previously defined empty load cases. By updating combination cases instead of computing them completely from the results of primary cases. above is used to multiply the spectral acceleration values to give the actual support acceleration to be used in the analysis.Response Spectrum Scale Factor The scale factor used in step 6. However. Many codes give spectral accelerations in a normalized form that have to be multiplied by site acceleration factors. the sum of the reactions for each dynamic load case will be displayed and you may enter factors that will be used to scale the results to ensure compliance with codes that require minimum base shears (step 7.4 and NZS 1170. Earthquake Design Code Spreadsheets The Excel spreadsheets AS1170_4. above).
being used to effect any required conversion. The spectral accelerations may be in normalized form or as absolute accelerations with a scale factor.. Period in seconds for the nth point on the curve. also in the library folder. Spectral acceleration for the nth point on the curve.. Microstran V9 14:Analysis • 265 .Response Spectrum Curves The digitized data for the response spectrum curves must be entered into the Response.. T(n) END Sa(1) Sa(2) Sa(3) Sa(n) where: Name T(n) Sa(n) String of alphanumeric characters used to identify each curve. Spectra.txt is available in graphical form in an Excel spreadsheet.. which resides in the library folder. This is a text file that you may edit to add additional response spectrum data. indicating the end of data for this curve. described previously. Keyword. The format of each set of data in the file is as follows: Name T(1) T(2) T(3) .xls. END The data in Response.txt file.
The error message is of the form: STRUCTURE UNSTABLE AT NODE nnnnn DOF f where: nnnnn f = = The node number at which instability was detected. Modelling problems of this type can usually be fixed by the addition of one or more node restraints to inhibit the gross displacement. If displacements are sufficiently large the analysis will be terminated with a message of the form: EXCESSIVE DISPLACEMENTS A solution can sometimes be obtained in cases like this by adjusting the analysis parameters but it is preferable to model very flexible tension members as cables. For example. Sometimes in linear elastic analysis a modelling problem may manifest itself as gross linear or angular displacement. 266 • 14:Analysis Microstran V9 . analysis will be terminated and an error message will be displayed on the screen. See "Tension-Only & Compression-Only Members" on page 97 and also "Instability & Ill-Conditioning" on page 72. The DOF number. This kind of problem may not be obvious in the member force plots but may be evident in the plot of displaced shape. In non-linear analysis very large displacements can occur in the analysis of structures containing very flexible tension members.Errors There are some types of error that only become evident during analysis and it is not possible for the consistency check to warn of this type of error before the analysis commences. as shown in the table below. The above error message may also be obtained where the automatic deletion of tension-only bracing members during non-linear analysis renders a structure unstable. if a structure is unstable because some part of it actually forms a mechanism. in which there was found to be no resistance to displacement.
The number format may be specified separately for translations. INPUT/ANALYSIS REPORT OPTIONS Microstran V9 15:Reports • 267 . or an RC Design report. Tables of structure data. This ability to select exactly what you want is particularly useful in reporting for large structures. members.15:Reports General Having selected Reports on the menu bar you may choose an Input/Analysis report. a Steel Design. Input/Analysis Report Options The report options dialog box is displayed when an Input/Analysis report is requested and this allows you to specify the tables required in the report. Reports are available at any stage of a job – tables of structure data may be produced prior to analysis. and load cases required. and other quantities. Several sample reports are shown in Chapter 20 – "Examples". loads. or results may be limited to the specific nodes. rotations.
a summary of minimum and maximum member forces. These reports may be very useful for design. giving 7 values for each result – at the end nodes and at 5 intermediate locations. With each minimum and maximum member force the load case is shown.. there are 5 segments in each member. With each minimum and maximum member force the member number and load case are shown. Node/member The selected loading/results will be sorted by load case number within node/member number. together with the co-existing member forces. Node/section With this setting node results are sorted by load case within node number and member results are sorted by load case within section number. Member summary (envelope) For each section. bending moment Mz) for which maxima and minima are to be reported. The adjacent check boxes allow you to independently include the member results in three different formats: • Member results For each member.g. With this setting you cannot select envelopes. a summary of minimum and maximum member forces. Sort by. member forces (and optionally displacements) for each load case. This is the only setting for which envelopes are possible. Section summary (envelope) For each member. • • 268 • 15:Reports Microstran V9 . By default.The options in the Style group determine the report type: Report At nodes or Along members You may report member results either at the nodes only or along the members (including the end nodes). Load case The selected loading/results will be sorted by node/member number within load case number. in section number order.. together with the coexisting member forces. There are additional intermediate points when there are concentrated loads. Only when you select results along members can you choose the number of segments in each member. If you check the Envelope check box you may then choose the member force component (e.
You may specify a list of load cases by entering a list and clicking the Use List button. When loading or results are included in the report options you must specify the load cases in the dialog box shown below. and sections). SELECTING LOAD CASES FOR REPORT For each table of loading or results selected in the report options dialog box you may specify the entities for which reporting is required. By default. Edit boxes are disabled if results were not requested for the corresponding entity. all items are selected with the ALL keyword.Limiting the Scope of the Report You may limit the scope of the loading/results tables included in the report by selecting load cases and entities (nodes. If a load case selection is in effect. members. In addition to a list of entities you may also specify a set containing these entities. this will be the default selection for the dialog box. ENTERING REPORT LISTS Microstran V9 15:Reports • 269 .
10. Load case summary. You may also use any legitimate combination of the keywords ALL. the total number of pages. Some examples of lists are shown in the table below: List 1. 5. the date and time of printing. For non-linear analysis the values of the analysis control parameters are also shown (see "Non-Linear Analysis" on page 247). and 6 Items 9 to 15 inclusive All items from 9 onwards All items up to 9 inclusive Items 5. Date and time of report. together with the load case type and a flag to indicate the type of analysis performed (or whether analysis was skipped). and the full path of the job.. 45. Structure type. Title Page A job summary on the title page contains the following information: • • • • • • • • • • • • Job name. Number of spring supports.6 9-15 9-9 5 TO 50 INC 5 ALL X 5 TO 10 Meaning Items 1. Number of nodes. Number of members.In entering a list you may use spaces or commas for separators. the job name. INC. . 20. 3. A hyphen is used to specify a range. the page number. Number of sections.3. the job title (two lines). and X. 15. This lists titles of all load cases reported. Title. TO. Microstran V9 • 270 • 15:Reports .. Number of primary load cases. Analysis type. Number of materials. Number of combination load cases. the program version. 50 All items excluding 5 to 10 inclusive Report Contents All pages record the name of the licensed user.5.
See "Fixed Supports (Node Restraints)" on page 87. the material number. As a rough guide. Sections Input by Property Values For sections input by specifying geometric property values. • • • • • • • Condition Number The condition number (CN) calculated during analysis is reported to give a measure of the degree of numerical accuracy that may be expected of the results. this table lists the section shape. and the defining dimensions. Section Properties This table lists the geometric properties of all sections defined in the input. and the comment field. 15:Reports • 271 Microstran V9 . the section number. Member Definition This table lists. name. while others are not. It is not possible to give a precise maximum allowable CN – some models that produce a CN of 104 are perfectly satisfactory. A large condition number is indicative of loss of numerical precision caused by modelling error. there may be a small discrepancy because of round-off in the fixed format of the report table. the orientation. See "Member Definition" on page 83. this table lists the section name and the comment field. Standard Shapes For sections input by specifying a standard shape. you should look carefully for signs of ill-conditioning if the CN approaches or exceeds 104. this table lists the library name. the member connectivity. the section name. (A "1" in the restraint code means that a restraint exists at the corresponding DOF). Table of Quantities The total length and mass are listed for each different section and for each different material.Structure Data Structure data is reported in the following tables: • Node Coordinates This table lists the global coordinates and the restraint code of all nodes in the structure. comment field. Normally. the release codes and the computed length. the orientation of the section (see "Section Properties" on page 88). for all members. Library Sections For each section extracted from a library. (A "1" in the release code means that a release exists in the corresponding direction). Material Properties This table lists the properties of all materials defined in the input. the values shown in the structure data tables will be identical to the input values but in some cases.
The diagram below shows positive displacement components. usually associated with excessive load residuals.The node number and the DOF at which the maximum CN occurs are reported to assist in the diagnosis of any problem. All nodes may be included (default) or lists of those to be included may be entered as set out above. 272 • 15:Reports Microstran V9 ..e. Microstran will request a list of nodes where displacements are to be reported. i. Displacements are measured with respect to the global axes and are positive in the positive axis directions. node displacements will not appear if results are reported along members. See "Instability & IllConditioning" on page 72 and Chapter 14 – "Analysis". POSITIVE DISPLACEMENT COMPONENTS Large values for some displacements may indicate ill-conditioning. The sum of the applied loads acting in each of the global axis directions is reported for each load case. Applied Loads For primary load cases applied loads are listed in the following groups: • • • • • GRAV loads Node loads Node temperatures Member loads Member temperatures For combination load cases the factors and titles of the component load cases are listed. The displacements for each translational and rotational DOF are reported for each node specified in the node list. Node Displacement Table Node displacements are reported if selected in the report options dialog box and if results are being reported at nodes.
Only selected load cases will be reported. The members for which member forces are reported may be selected as set out above. Report at Nodes Member forces acting on the ends of the selected members will be tabulated for each selected load case if reporting of results at the nodes was selected in the report options dialog box. Microstran V9 15:Reports • 273 . Shear Force (Fy. That is. the offset from the "A" end is listed. the member tends to sag. These are absolute displacements. and Z axes. Torque (Mx) End "B" of the member rotates in a positive sense relative to end "A". Mz) Tensile strain occurs on the underside of the member (with respect to the member axes). For each member. The sign convention for member forces is such that positive member forces cause the following strains or displacements in the member: • • Axial Force (Fx) Tensile strain. it is necessary to specify the member force component and Microstran tabulates the minimum and maximum values of the specified component for the selected load cases.Member Force Tables Member forces are listed if selected in the report options dialog box. Bending Moment (My. Fz) End "B" of the member deflects in the positive y or z direction relative to end "A". The number of segments to be used for calculating the intermediate values is also selected in the report options dialog box. In this case. • • See "Sign Conventions" on page 64 for a diagram showing the directions and the effects of positive member forces. Member Force Envelope Member force envelopes may be selected in the report options dialog box. Report Along Members Member forces and displacements will be tabulated for each member selected on the member list if reporting of results along members was selected in the report options dialog box. the "A" and "B" node numbers and the section number are listed. followed by all force components at that position. Displacement components are tabulated as: • Global Components Parallel to the global X. At the end of each segment in the member. Y.
Pey The Euler load for the member for buckling about the member y axis. is reported for each primary load case when reactions are included in the report. All forces are taken into account. The elastic critical load factor is shown for the particular load case. This is the factor by which the input loads must be multiplied in order to obtain the elastic critical load of the structure for the load case. For each member. The support nodes at which reactions are shown are listed as set out above. 274 • 15:Reports Microstran V9 . These are the forces necessary to ensure the equilibrium of the structure. Each value should be equal to and opposite the sum of the applied loads in the direction of the respective axis. Large residuals indicate that the structure is ill-conditioned. Pcrit The load in the member at the elastic critical load condition. Reactions Table Reactions will be tabulated at support nodes if selected in the report options dialog box. The residual is obtained by subtracting the product of the structure stiffness matrix and the node displacement vector from the static equivalent of the applied loading at each node in the structure. Sag is measured in the direction of the load resultant on the cable. The table of reactions gives the forces acting on the structure at the support nodes. including those applied directly to restrained DOF. or "out of balance" force. The sum of the reaction forces acting in each global axis direction are also reported. the following items are tabulated: • • • Length Computed from end node coordinates. Residuals Table The maximum residual. This table will be included if you selected effective lengths on the report options dialog box. the residuals should be small in comparison with the applied loading. In all cases.• Local Components Parallel to the transverse member axes y and z. a table of critical loads and effective lengths is available. These components are reported relative to the chord (the line joining the displaced end nodes of the member). Effective Lengths Table For elastic critical load analysis. For cables sag is tabulated instead of these two components.
so choosing the Reports > RC Design command will simply display a warning to this effect. Design Report Options Steel Design Report This dialog box allows you to specify what kind of steel design report is required. STEEL DESIGN REPORT OPTIONS RC Design Report RC design reports are produced automatically when RC design is run. see "Elastic Critical Load Analysis" on page 255. Microstran V9 15:Reports • 275 .• ky The effective length factor for the member for buckling about the member y axis. kz The effective length factor for the member for buckling about the member z axis. Pez The Euler load for the member for buckling about the member z axis. • • For more information.
fixed field or comma-separated. First line (comma-separated format): Headings. First line (fixed field format): Number of nodes. member end forces. Following lines: Member number.nd where "Job" represents the job name) contains the node displacements for each load case. The member forces are output with an internal sign convention where positive forces act in the positive member axis directions. such as Excel. which may be input to other programs or imported to spreadsheet programs. You should occasionally review them in Explorer and delete any that are no longer required. The files required are selected in the dialog box shown below. Node Displacements File This file (Job. 276 • 15:Reports Microstran V9 .mf where "Job" represents the job name) contains the member force components at the ends of each member for each load case. load case number. number of load cases. By selecting File > Export > Results File command. you may produce formatted text files of output results. The formats of the results files are as set out below. etc. load cases. First line (comma-separated format): Headings. First line (fixed field format): Number of members. These files may be in either of two formats. (User programs may create input data for Microstran by means of the archive file – see Chapter 9 – "Archive File Input". members. Member Forces File This file (Job. number of load cases. are formatted without a decimal place while real values may be in floating point or exponential format.) EXPORTING A RESULTS FILE Numbers of nodes.Exporting Results Results files remain in the data folder after you close Microstran.
Reactions File This file (Job. reactions. load case number. load case number. First line (comma-separated format): Headings. number of load cases. Following lines: Node number.rc where "Job" represents the job name) contains the node reactions for each load case.Following lines: Node number. node displacements. First line (fixed field format): Number of restrained nodes. Microstran V9 15:Reports • 277 .
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16:Steel Member Design General STEEL DESIGN TOOLBAR There are optional steel design modules that allow you to design and check steel members in a Microstran model in accordance with various steel design codes. The steps required prior to designing or checking members are: • • • • Analyse the structure. Specify the load cases to be used in the design. Initialize design members. The Design > Update Sections command allows you to replace sections in the analysis model with those chosen from the design results. Note: You must use kN and meter units in your Microstran model if you are going to use a steel design module. Modify design data as required. Microstran V9 16:Steel Member Design • 279 . Most of the data required for a design is obtained directly from the model but additional information such as steel grade and cross-section restraints must be input. Once entered. this data is saved automatically when you save the Microstran job and when you export to an archive file. When this is done the analysis should be repeated to take account of any redistribution of member forces before a final design check.
0. which must be less than or equal to 1. Europe. Library files may be edited and special section libraries may be created. AS 4100 and NZS 3404 use the load factor (the ratio of capacity to load). See Chapter 18 – "Section & Material Libraries". f/F). Allowable stress codes use the stress ratio (the ratio of actual to allowable stress. which must be greater than or equal to 1. and angle sections may be taken into account automatically in the design module. Note: To express the adequacy of members. If an elastic critical load analysis has been carried out you may choose to use automatically computed values for the effective lengths of compression members instead of specifying k factors. Assigns default design data to initialized members. Analysis The choice of linear or non-linear analysis should be based on design code requirements. where appropriate. Other limit states design codes use the utilization ratio.0. Britain. Library files containing sections used in Australia. 280 • 16:Steel Member Design Microstran V9 . Additional moments caused by eccentric connections at the ends of channel. New Zealand. tee.0. Initializing Design Members DESIGN > INITIALIZE DESIGN MEMBERS Initializing design members performs three necessary functions: • • • Associates each initialized member with a specific steel design code. and USA are available.Section Library Design modules select sections from the configured steel section library. Japan. which must be less than or equal to 1. Links analysis members together into design members.
Linked members must satisfy these conditions: • • • • They must be collinear (or almost so). Key concept. Use the Query > Design Member command to determine which analysis members are included in any design member. The Initialize Design Members > Linked command initializes the selected members as linked design members if possible. The default member design data is displayed and may be altered for each group of members being initialized. The member design data must be edited for any member where the default member design data is not correct. Interior nodes that do not have twist restraint make it necessary to link analysis members together forming a design member. On initialization. Use the Design > Design Data command to do this. Microstran V9 16:Steel Member Design • 281 . Member selected that do not satisfy these condition will be initialized unlinked.Key concept. It is often convenient to select all the steel members in the structure that have to be designed and allow Microstran to link eligible members automatically. You may re-initialize any design member if you want to remove the linking. Use the Initialize Design Members > Not Linked command if you want each selected analysis member to be a design member. Default member design data. They must have the same section number and orientation. Their longitudinal axes must be in the same direction. Twist restraint is then assumed at each end of each analysis member. is specified with the File > Configure > Steel Design command. They must have no releases. including the steel design code. Compression members that are not cantilevers must be linked so that design members span between positions of lateral restraint. no twist restraint is assumed at intermediate nodes in linked members. Key concept. In Microstran every design member that is not a cantilever has twist restraint at each end. If this twist restraint does not exist unlinked initialization is not valid and you may obtain unconservative results.
In the first dialog box. choose the design code from those available in the list box.Design Data DESIGN > DESIGN DATA On selecting the Design > Design Data > Input/Edit command Microstran highlights in turn all the members so you can enter steel design data in a series of dialog boxes. 282 • 16:Steel Member Design Microstran V9 . CHOOSING THE DESIGN CODE The next step is to enter basic design data for the selected member in the button at the top of the dialog box shown below. You may click the dialog box for detailed information about each item.
select "Fy =" and enter the yield stress and the ultimate tensile stress in the edit boxes. Depth range Only sections with depths between the minimum and maximum values specified will be considered during design. To determine whether a member is adequate the design ratio (i. Grade Select a grade from the list box. rectangular and square hollow sections. There are design rules for I and H sections (rolled and welded). channels. Each particular configuration of compound section to be considered (e. a load factor or a stress ratio. circular hollow sections.g. UB. Section types are described by mnemonics (e.0. The time required to search for a satisfactory section during design will be reduced if the minimum depth is increased to a realistic value. tee sections. gap. • • • Microstran V9 16:Steel Member Design • 283 .e. the intercomponent shear is not checked. RHS SHS – The section may be either an RHS or an SHS. Acceptance ratio This is the limiting acceptance ratio – normally 1. component designation. For compound sections. angles. and packer spacing) must be included in the steel section library. UC). If you do not want one of the listed grades. and compound sections.DESIGN DATA The dialog box contains the following items: • Select from these types A list of the section types to be used in design. depending on the design code) is compared to this value. Only the grades actually available for the selected section types are shown.g. A member is adequate if its load factor exceeds this value or its stress ratio is less than this value. A space or comma should separate individual mnemonics. Examples of the selection list are: UB – Only UB sections will be considered.
Specify whether webs will be checked using the combined stress provisions of Appendix I. The effects of eccentricity for tension members is taken into account by code rules that reduce the effective cross-sectional area. For angles. For AS 4100 and NZS 3404 they are also used in the computation of moment amplification factors where linear elastic analysis has been used. giving rise to additional bending moments that must be considered in design (not applicable to hollow sections). For unlinked design members start is the "A" node and end is the "B" node. you must specify whether the connection is concentric or through the long leg or the short leg. • • • • • 284 • 16:Steel Member Design Microstran V9 . specify whether the section is connected concentrically or through the web or the flanges. column slenderness The maximum l/r ratio permitted. specify whether the tee is connected concentrically or through the flange. The net area of the section will be obtained by deducting the cross-sectional area of the bolt holes. The sidesway flags are used to determine the effective length for the computation of in-plane capacity. the leg parallel to the section XX axis is considered to be the "short" leg. Often 180 for columns and 300 for beams – use zero if l/r is not to be checked. For tee sections. Sidesway Check a box to specify that sidesway is permitted about the respective section axis. The width of bolt holes should be determined in accordance with the design code and should take into account the possibility of diagonal failure lines. Eccentric connection moments are considered for compression design only. Max. For linked design members the start is the exterior node of the first member in the linked list and the end is the exterior node of the last member in the linked list.• Cantilever Check a box to indicate that either end of the design member is a cantilever. Effective width of bolt holes The total effective width of any bolt holes in the flanges and webs of the members. Appendix I For AS 4100 and NZS 3404 only. For an equal angle. The rules of Appendix I are not usually applied to standard sections used in building structures. For channels and I sections. Connected elements Specify whether the member is connected eccentrically with respect to the centroidal axis.
LATERAL RESTRAINT DATA The items in the table are: • Offset The distance from the end of the design member to the cross-section where the lateral restraint is being specified. When the section XX axis is aligned with the member y axis. Any offset value may be changed as long as all offsets remain in ascending order. / Btm Flg. At each restraint position you must specify the restraint at the top and bottom of the member. the offset distance is measured from the end of the rigid offset. The top of the member is defined as the +y face (y is the member axis usually aligned in the plane of the web of an I section – see "Coordinate Systems" on page 63). Delete an offset by highlighting it and clicking the Del. and any restraint provided for column action. Key concept. button. 16:Steel Member Design • 285 • • Microstran V9 . Top Flg.Lateral Restraint Data Lateral restraints may be added at any point along a design member. Use the View > Display Options command to show the y axis for all members. Where there is a rigid offset at the end of the member. N – No restraint. button. Node Where the position of the lateral restraint corresponds to a node the node number is shown in this column. C – Continuous lateral restraint. You cannot change this value. The dialog box shown below is used to specify the lateral restraint data for a particular design member. Lateral torsional buckling (LTB) restraints are defined with the following codes: L – Effective lateral restraint. the top of the section is the +z face – see "Selection from Library" on page 89. not the node. You may insert a new restraint position by highlighting the row of the next offset and clicking the Ins.
SHS). the computation of the moment amplification factor if linear elastic analysis has been used. For end-restrained beams under gravity loads. The member effective length is calculated as k × the distance between column buckling restraints. If you change column restraints during member design ECL analysis results may not be correct. • Load Height Specify whether the load height position is such as to Stabilize or Destabilize the critical flange of the beam during beam bending. The results from an ECL analysis will only be applicable if the model includes all member restraints relevant to column action. loads applied to the top flange are destabilizing while those applied at the level of the shear centre or below are stabilizing. kx and ky kx and ky are the effective length factors for column buckling about the section XX and YY axes respectively. repeat the ECL analysis after any change to the column restraints. ECL analysis results must be Microstran V9 • • 286 • 16:Steel Member Design . Usually.R – Plan rotational restraint. The effects of destabilizing loads are taken into account in most design codes by increasing the effective length for bending. a flexible bracing member connected to a beam at midheight does not constitute a beam restraint that meets code requirements for cross-section restraint and so should be ignored when determining the effective segment length for out-of-plane buckling (LTB). Buckling restraint is specified independently for each restraint position. In this case. any bracing that provides cross-sectional restraint will also provide restraint against buckling about the minor section axis but the converse may not be true. The segment length to which the k factors apply is delimited by checked boxes.e. ECL analysis results will be most useful for structures modelled as plane frames where all out-of-plane action is restrained. The effective length is required for the determination of nominal capacity for members in compression and. for some design codes. A checked box is required at restraints against column buckling and also at the end of a cantilever. Column Buckling (In-Plane) Restraints Specify the location of restraints against column buckling about the major and minor principal axes of the cross-section.. Note: LTB restraints are ignored for sections not subject to lateral torsional buckling (i. you may enter "ECL" in the kx and ky fields to have effective lengths computed from the elastic buckling load factors (λc). Loads applied at positions of restraint are always stabilizing. Results from ECL Analysis If results are available from an elastic critical load (ECL) analysis. CHS. E – Elastic lateral restraint (provides twist restraint in combination with "L" restraint on opposing flange). For example. This code was "P" in previous versions of Microstran.
You may click on the button and then on any item in the dialog box for a pop-up help window. You may manually input effective length factors if you do not wish to use the values derived from the ECL analysis. GRAPHICAL DISPLAY OF LATERAL RESTRAINTS Microstran V9 16:Steel Member Design • 287 . See "Elastic Critical Load Analysis" on page 255. POP-UP HELP Graphical Display of Restraint Data You may display a diagrammatic view (see below) of a steel design member by right-clicking on it and selecting the View Steel Restraints command on the context menu. Effective length factors for out-of-plane column buckling cannot be computed if the structure has been modelled as a plane frame.available for all the load cases nominated for design.
The design restraints are represented by the following symbols: • • • • • • Red cones – XX column buckling restraint. Blue cones – YY column buckling restraint. Green rods – effective lateral flange (LTB) restraint. Broken green rods – elastic flange (LTB) restraint. Green pyramid – rotational restraint of flange. Green triangles – restraints continuous over segment.
Nodes are shown as orange spheres and member numbers are shown in magenta above the top flange. The section axes XX and YY are shown, together with the member axes of the first link in the design member. In classifying the restraint condition at a section, each physical restraint is interpreted according to whether the flange where the restraint occurs is critical. The Steel Restraints button on the Steel Design toolbar displays lateral torsional buckling restraints for all steel design members. Note that column buckling restraints are not shown. LTB restraints are shown as a short grey line at the flange positions of the member. The offset from the member is not to scale. "L" type LTB restraints are shown in a darker grey than those of type "E".
Steel Restraints
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Selecting Design Load Cases
You must select the load cases to be considered in the steel design. All load case titles are shown in a list box and you may select any of these by clicking on them. Sometimes, it might be more convenient to enter a list of load case numbers rather than selecting graphically. To do this, enter the list in the List edit box and click the Use List button. The rules for lists are set out in Chapter 15 – "Reports".
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The Design Process
Check The selected members are checked. Check All All steel design members are checked. Design A steel section is automatically chosen from the library for each of the selected members. The lightest suitable section is chosen independently for each design member. You may use this type of design as a basis for rationalizing section numbers throughout the structure in readiness for a final design using the Design by Group command. Design by Group The section numbers define groups of members for which a single section will be chosen. Group design proceeds by alternate design and check cycles on successive members in the group until the lightest section that will be satisfactory for all members in the group has been chosen. Member groups may comprise single and linked members.
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Updating Sections
For structures that are statically indeterminate, the internal forces in each member depend on the relative stiffness of the member. If the sections selected in the design are significantly different from those that were assumed for the analysis, you may update the input data by selecting the Design > Update Sections command. For each design group a dialog box (see below) displays all the different sections designed for members of the group. You may choose one of these sections, the original analysis section, or any other section from the library. After re-analysis, you may check the design. On second and subsequent design cycles it is best to operate in check mode and to use design mode only for those members that fail the check.
Microstran computes member forces at a number of points along the member, including the ends of the member, points of application of concentrated loads, and all points of torsional restraint. Corrections are made to the analysis moments for eccentric connection and, for angles where rectangular axis properties were selected, the moments are resolved into the directions of the principal axes. Note: Microstran Steel Design does not check torsion or bearing. Additional manual checks must be made for any member that is subject to significant torsion or high bearing forces.
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Obtaining Design Results
After checking or designing members the design results may be displayed or reported in a number of ways: • Use the Results > Design Ratios command to display design results with members colour-coded to show the percentage of member capacity actually utilized in the critical load case. With this display, all members that have failed a design check are shown in a shade of red. Click the Legend tab the output window to display the colour bands being used. Use the Query > Design Member command to show a summary of design results in the output window for any selected member. Use the Reports > Design command to create a design report. Members to be included in the report may be selected with the mouse or all members may be selected by checking the All members option button in the dialog box. The design report may be previewed with the File > Print Preview command and it may be printed with the File > Print File command. Note that there are extensive facilities for formatting the design report using the File > Page Setup command.
• •
Steel design results are saved when you save a job but the steel design report file is automatically deleted (if it exists) when the job is closed. The steel design report file is created in the data folder and it is named Job.p4, where "Job" is the job name. You may save a steel design report file by dragging it to another folder using Windows Explorer.
Steel Detailing
Information may be exported in SDNF format for transfer to third-party steel detailing programs (e.g. Xsteel, Strucad). Member design must have been performed prior to selecting these output options.
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17:Steel Connection Design
Steel connection design is an extension of the steel member design option that allows you to choose connection types for any design member and then check the connection. The steel member design and connection design options must both be available. Each connection type has default data to minimize input of design data. The connection dialog box may be displayed by right-clicking on the design member at the connection location. Any design member may have a connection at each end and a single splice at a specified distance from the start of the design member. In some cases you have a choice of which design member you allocate the connection to – for example, an apex connection in a portal frame may be associated with either rafter. It does not matter which member the connection is associated with but you should not input the same connection twice. Microstran's virtual reality window shows the structure with the steel connections. The connection dialog box can also be displayed by rightclicking on a connection in this view.
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Virtual Reality Graphics in Microstran
An important feature of Microstran is its virtual reality (VR) view. When the connection design option is available this graphical representation may include every detail of each connection in the model, right down to the welds and markings on the bolts. Each connection is shown in the connection dialog box in a standard position. When the same connection is shown in Microstran it must be moved into the position where it exactly fits the rest of the structure. This usually means that the connection appears in Microstran with a different orientation from that shown in the connection dialog box. Initially, when you drag the mouse, the structure rotates in the drag direction about the centre of the structure. Double-click on any point on the displayed model and that point becomes the new centre of rotation. If the double-click location is not on the structure the structure may disappear – in this case, press Esc to revert to the initial view. You may pan the view by dragging with the right mouse button and you may zoom with the mouse wheel or the Page Up and Page Down keys.
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respectively. which may be a column or a beam. Moment Connections Moment connections available are: • • • • Microstran V9 BMEP – ASI* bolted moment end plate HBEP – ASI* haunched end plate WBC – ASI* welded beam/column MEPC – AISC† moment end plate connection 17:Steel Connection Design • 295 . The flag is green when the strength ratio is 1.A pop-up menu appears when you right-click the stationary mouse anywhere on the structure (if the mouse is moving you will pan). red when it is less than 1. The File menu for the VR view allows you to save a . Keyboard shortcuts for these commands are J and P. This menu lists keyboard shortcuts to toggle display items. These are: • • • WSP – Web side plate (also known as a fin plate or shear tab) ACLT – Angle cleat FEP – Flexible end plate These connections can be selected at either end of any horizontal I section or channel design member. Simple Shear Connections Three simple shear connections are available.JPG file of the image or print the image.0. At locations where you specify shear connections you should ensure that the Microstran model has a moment release or negligible bending moment. The connection design ignores any bending moment in the Microstran model. and black when the connection has not been checked. Microstran identifies the support member. Connection status flags show the connection number on one side and the connection strength ratio (load factor) on the other – type R to reverse the flags.0 or greater. C – Connections X– F– N– S– Connection symbols Connection status flags Node numbers Node symbols M – Member numbers It also allows you to display node or member property dialog boxes and change or check a connection.
Microstran identifies the support member. 296 • 17:Steel Connection Design Microstran V9 . This can cause difficulty because connections cannot be input for members that are not design members. The MEPC and FPC connections can only be in horizontal members. The distance from the start of the design member must be specified. Only axial forces in the bracing member are considered. To input the haunched connection in this situation you must select a remote HBEP connection at the end of the prismatic rafter. and X or K bracing members all connected together are not yet available in Microstran.• FPC – AISC† flange plate connection (welded or bolted) * † Australian Steel Institute model American Institute of Steel Construction model These connections can be selected at either end of non-vertical I section design members. They are checked ignoring the effect of member forces in the column and any other beam connected to the column. Column stiffeners may be specified for any of these connections. Bracing Connections Microstran permits several types of single bracing connection. The splice location does not have to coincide with a node. Column actions and actions from other beams connected to the column are ignored. Only the connection between the beam and the column is checked. Bracing connections comprising beam. Splices Splices available are: • • • BMEP – ASI bolted moment end plate BSPL – ASI bolted splice WSPL – ASI welded splice A single splice may be included for any I section design member. These allow you to check the connection between a bracing member and a cleat or gusset plate. Location of Haunched Connection Haunched rafters may be modelled as a prismatic rafter and one or more larger sections representing the haunch. column. The prismatic part of the rafter would be a design member but the haunch members may not be. which must be a column oriented so that the connection is to the column flange.
Microstran V9 17:Steel Connection Design • 297 .Base Plates Pinned and moment base plates are available. You should not specify a moment base plate at a pinned support or a pinned base plate at a support where there is bending moment. Base plates are permitted only at vertical column supports.
For the X connection. If Microstran detects this condition for any load case an error message is displayed. Limitations of the K/N Connection Model The models for the K/N gap and overlap connections are only valid for one bracing member in tension and the other in compression. Whether K/N connections with zero eccentricity are gap or overlap connections depends on the geometry of 298 • 17:Steel Connection Design Microstran V9 . Eccentricity is positive when measured towards the outside of the chord and negative towards the inside. For HSS truss connections Microstran evaluates all relevant member forces at the connection and transfers to the connection dialog box all resultants necessary for checking the connection according to the connection design model. The types of HSS truss connection available are: • • • K/N overlap or gap connection X connection Y/T connections K/N and X connections have two bracing members. the two members with the greater section depth are assumed to be the chord members. If the chord and bracing sections are of the same depth the member associated with the connection is assumed to be a chord member. A node load occurring at the connection may result in both bracing members being simultaneously in tension or compression. referred to in the connection dialog box as brace 1 and brace 2. This is because the members in each chord form a single design member that can have connections only at its ends. while the Y/T connection has only one. all K/N truss connections are shown in the connection dialog box with a zero chord eccentricity. thus invalidating the model. Every member in the truss must have its member y axis in the plane of the truss and must be defined as a steel design member.HSS Truss Connections General HSS truss connections are available for trusses located in a vertical plane. Where chord members have been initialized linked it is necesssary to associate the connections with bracing members. Initially. Noding Eccentricity The eccentricity at a connection is the distance from the intersection of the bracing members to the centre-line of the chord. Each connection is associated with one of the design members at the joint.
The values of gap or overlap corresponding to zero eccentricity may not be admissible in the connection design model – for example. Microstran V9 17:Steel Connection Design • 299 . the bending moment caused by noding eccentricity must be considered. in an overlap connection the overlap must be at least 25% but cannot exceed 100%. This means that a connection specified in Microstran as a K/N overlap connection may appear in the connection dialog box as a K/N gap connection. The bracing members in the Microstran model for an HSS truss often include pins (moment releases) at each end but bracing member bending moments are usually negligible without them.the truss. it is not considered in the HSS truss connection models. however. Discontinuities will be visible in the Microstran VR view between a connection and the rest of the structure if the eccentricity in the Microstran model does not equal that in the connection. a connection specified in Microstran as a gap connection may appear in the connection dialog box as an overlap connection. the gap or overlap would be specified to give the desired connection detail but the resulting eccentricity must then be considered. It is necessary to introduce rigid offsets in the chord members to ensure that the chord design moments are consistent with the connection eccentricities. and indeed. Usually. Chords The HSS truss connection models take into account bending moment in the chords caused by transverse member loading but that caused by noding eccentricity may be ignored provided that the eccentricity is within the prescribed limits. When you edit a connection you may set the eccentricity as required and the connection type will be adjusted accordingly. Unless rigid offsets are specified in the chord members the eccentricity in the Microstran model will be zero. Similarly. Joint Bending Moments Bracing Members Bending moment is usually not significant in the bracing members of a truss. For design of the chord members.
Using Steel Connection Design Note: You must use kN and meter units in your Microstran model if you are going to use steel connection design. the offset from the start of the member. the only available connection types are the pinned and fixed base plate. Please refer to Chapter 16 – "Steel Member Design" for detailed information. Update design member sections as required. Input Connection Data The only item of connection data required in Microstran is the connection type. Steel Member Design Before using integrated connection design you must have used an optional steel design module to check all design members. On the right of this box the number of connected members. CONNECTION TYPE DIALOG BOX 300 • 17:Steel Connection Design Microstran V9 . The connection number allocated by Microstran is shown to the left of the box showing the connection type. is shown. Not all connection types are displayed in the drop-down list boxes because any types that are not feasible are automatically suppressed. and for a splice. Modify design data as required. for example. Final check of all design members. Check all design members. The steps required are: • • • • • • • Analyse the structure. Initialize design members. Specify the load cases to be used in the design. not including the connection member. The dialog box below is displayed for each design member where you wish to add a connection. At the bottom of a column.
A connection dialog box is then displayed for each connection in turn. If an inappropriate connection has been chosen an error message will normally be displayed when you check the connection. The dialog box for some simpler connections contains a Design button. CONNECTION DIALOG BOX You may change any connection detail or dimension. You may check connections one at a time by right-clicking on a design member and selecting Check Steel Connection from the pop-up menu. which iteratively changes the connection parameters. You may also go straight to this dialog box by right-clicking any design member and choosing Steel Connection Type on the pop-up menu. If you click the Cancel button any changes made in the dialog box are abandoned and the dialog box is not displayed for any remaining selected connections. Check Steel Connections The next step in connection design is to select the Design > Steel Connections command and then click on all design members whose connections are to be checked. After selecting these design members.This dialog box is displayed after the steel member design data dialog boxes when you select the Design > Design Data > Input/Edit command. It is your responsibility to ensure that the final connection configuration is satisfactory in every way. This may not always give a satisfactory design. searching for a configuration that passes all strength checks. right-click and choose OK on the pop-up menu. When you click the OK button in the connection dialog box the connection details are saved and the dialog box is displayed for the next connection. Where you right-click on the design member determines which Microstran V9 17:Steel Connection Design • 301 .
Limcon collects the Microstran connection files for the job and shows all the connections together. Each end quarter of the design member selects the connection at the end if it exists and the middle half of the design member selects the splice if it exists. Step 1 – Check steel member design results The status of the steel member design can be checked by clicking the Design Ratios button on the Results toolbar and the Display Results Values button on the Results toolbar. Any changes you make to the connections at this stage will be inaccessible to Microstran. you may display a VR image of the whole structure including connections by clicking the Virtual Reality View button. Interaction with Limcon If the Limcon program is available you can see all the connections for a Microstran job in a single view by starting Limcon with this command line: Lmc3. Step 2 – Choose connection type 302 • 17:Steel Connection Design Microstran V9 . The report may be previewed with the File > Print Preview command or printed using the File > Print File command. Report A detailed report for selected connections is available with the Reports > Steel Connections command.exe /ALL=jobname Where "jobname" is the Microstran job name. Display Steel Connections Having checked all the connections in the job. The shortcut must start Limcon in the Microstran data folder. In the initial view connections are not shown – type C to redraw the view including connections. This shows design members colour-coded according to the design ratio. Connection Design Example The following step-by-step example illustrates the design of a knee connection in the portal frame from Example 2 in Chapter 20.connection is checked.
The end plate has been sized to match the rafter and column members. Microstran V9 17:Steel Connection Design • 303 .Right-click on rafter near the knee joint and select Steel Connection Type. Select the bolted moment end plate connection type. Notice in Check 1 that the bolt gauge is less than the recommended value of 140 and in Check 22 that the stiffener width is less than the recommended minimum of 99. Step 3 – Modify connection as required Click the Expand button to inspect the connection check output. Step 4 – Display VR image for structure with connections Click the OK button to dismiss the connection dialog box and in Microstran click the Virtual Reality View button. Type F to display connection flags and R to reverse the flags showing the connection load factor. The connection design dialog box displays the initial configuration. other data items remain at default values. Step 3 – Initial check of steel connection Right-click on the rafter again and select Check Steel Connection. Change these values and then click OK. The resulting view is shown below.
Step 5 – Print output for connection Click the Print button to output the design check for the connection. This output is shown on the following pages. 304 • 17:Steel Connection Design Microstran V9 .
Microstran V9 17:Steel Connection Design • 305 .
306 • 17:Steel Connection Design Microstran V9 .
Microstran V9 17:Steel Connection Design • 307 .
308 • 17:Steel Connection Design Microstran V9 .
An "X" character contiguous with the section mnemonic is part of the section mnemonic. and design of steel members.g. The File > Configure > Section Library command allows you to select any available library as the current library. is the only part of the name that may be alphabetic. checking. It is embedded in the section name and. For each library file there is a corresponding source file. Apart from the section mnemonic. Asw. "200UB25. Microstran V9 18:Section & Material Libraries • 309 . Library source files may be manipulated by the Section Library Manager. printed. and "XXBOX100" (mnemonic exceeds 4 characters). "X" characters with numeric characters before and after may be included in the section name. or edited. apart from "X".9X2. Section Mnemonic The section mnemonic is used in Microstran for specifying sections to be chosen automatically in design.lib. Examples of valid section names are. Ukw. and "W14x311". Blanks are not permitted. an ordinary text file having a file name extension "asc". "CTT380X100".4". Using the method described below you may edit the library. This is the section mnemonic. "88.4H1" (two separate alphabetic groups).4" (leading X). The section name must have one contiguous alphabetic group between 1 and 4 characters long. Invalid names include "200UB25. "100XX". "CTT380X100X" (trailing X). "X200UB25.6CHS". Special section libraries may also be created.lib) and cannot be listed. "XX100". Section Library Microstran's library files have the file name extension "lib" (e.18:Section & Material Libraries General Microstran refers to the current steel section library for information required for analysis. Section Name Each section has a unique section name with up to 15 characters.
however.When adding new sections to a library you may choose any suitable section mnemonic. DT 1 2 3 4 5 6 7 8 9 10 11 12 16 22 13 17 18 19 20 21 24 310 • 18:Section & Material Libraries Mnemonic Section Type TFB UB. Section Categories Each group of sections in the library is assigned a section category. WC RHS SHS CHS PFC BT. together with some of the common section mnemonic codes for these types. back-to-back DuraGal cold-formed angle Microstran V9 . CT EA UA DAL DAS STA QAN UBP TFC ROD BAR CTT CBB CA Taper flange beam Universal beam or welded beam Universal column or welded column Rectangular hollow section Square hollow section Circular hollow section Parallel flange channel Tee section Equal angle Unequal angle Double angles. toes together Double channels. When choosing a section. short legs together Starred angles Quad angles Universal bearing pile Taper flange channel Round Rectangular bar Double channels. The table below lists valid design types. may not be used as a section mnemonic because the section name would then be confused as a number in exponential format. Every section in a section category must have the same section mnemonic. A single character "E". Design Type For design purposes each section is classified according to its design type. The section category number is shown in the library source file under the heading SC. All sections within a category must have the same design type and section mnemonic. WB UC. The design type is used to interpret the section properties and it determines the applicable design code rules. you first choose the section category and Microstran then displays all the sections in the category. The design type number is shown in the library source file under the heading DT. long legs together Double angles.
enter it as G1 and enter zero for G2 and G3. Up to three grades. AS 4100) require information about the level of residual stresses in a section. G1.25 30 33 34 39 40 41 42 43 44 45 46 47 48 49 50 51 52 CC UI BOX LSB DLSB PEA PUA PC DPC LC DLC RLC DRLC PZ LZ DHS DDHS DuraGal cold-formed channel Section with analysis properties only Unsymmetrical I section Box section OneSteel LiteSteel™ Beam Double OneSteel LiteSteel™ Beam Plain cold-formed equal angle Plain cold-formed unequal angle Plain cold-formed channel Double plain cold-formed channel Cold-formed lipped cee Double cold-formed lipped cee Cold-formed return lipped cee Double cold-formed return lipped cee Cold-formed plain zed Cold-formed return lipped zed Dimond Hi-Span™ section Double Dimond Hi-Span™ section Steel Grades Microstran determines yield and ultimate tensile stresses from recognized steel grades. Residual Stress Code Some design codes (e. G3 must be zero.g. and G3. may be included for each section. If there are two grades available. f 1 2 3 4 5 Section Type Stress relieved Hot-rolled Cold-formed Lightly welded Heavily welded Microstran V9 18:Section & Material Libraries • 311 . G2. If there is only one grade available for a section. This is provided by the parameter designated "f".
Section Properties Dialog Box The properties of any section in the destination library may be displayed by right-clicking the section and choosing Section Properties on the popup menu. is shown on the right while all available library source files are shown on the left. or section on the left and click the arrow button to send it to the destination library on the right. 312 • 18:Section & Material Libraries Microstran V9 . Doubleclicking a section on the right will display a dialog box in which you may alter any value. Double-clicking the section will also display the section properties dialog box. you will lose your changes when you next update library files. You may edit any library source file supplied but it is preferable to make a copy and edit that – otherwise. A tree view of the destination library. Each library may be expanded to show the section categories and each of these may be expanded to show the sections contained in the category. Clicking the Compute button computes all derived values from the current dimensions. The Restore button sets all edit boxes back to their original values.Section Library Manager Library source files may be manipulated by the Section Library Manager. either an existing library source file or a new one the dialog box below is displayed. SECTION LIBRARY MANAGER You may select any library. Click the button at the top and then click on any item for help. empty if new. The dialog box shows all the values stored in the library for the section. Any values that are not disabled in the dialog box may be changed. After you have selected the destination library. category.
Ax is the nett "web" area where the web is considered to include both sides.SECTION PROPERTIES DIALOG BOX FOR CHANNEL Section property dialog boxes for some sections have an Ax. Note: Shear areas are usually set to zero. This report lists any errors or inconsistencies detected in the input data. For SHS. Ay is the nett area of the top and bottom "flanges" – this does not include overhang in the case of the box section. When compilation has finished successfully a report is displayed. Click Yes in the dialog box below to do this. Compiling a Library When you click the Save button you can initiate the compilation of the library source file into a Microstran library. RHS. The library report for Microstran V9 18:Section & Material Libraries • 313 . For an I section Ax is computed as the nett web area and Ay is computed as 5/6 of the flange area. causing Microstran to ignore shear distortion. COMPILING THE LIBRARY The library compiler reads and interprets the library source file and writes a Microstran library file. and box sections. The value of any section property value input as zero is computed automatically provided sufficient dimensions for the calculation have been input. which computes shear areas. as shown below. Similarly. Ay button.
the current library may be printed or previewed from the Microstran File menu. a warning message results. COMPILING THE LIBRARY – REPORT 314 • 18:Section & Material Libraries Microstran V9 . All section property values are computed from the section dimensions and where the corresponding input value differs by more than 1%. Note: Microstran and Limcon libraries are compatible. Section properties are computed only approximately for taper flange sections so warnings for these sections may not be valid.
0 1. kg/m3.1 $ File is free format $ $ <matl name> <Young's mod> <Poisson's ratio> <mass density> <coeff expansion> $ STEEL 200E3 0. 850. F27 18500 0. 650. 0. This initiates editing of a library source file in Microstran's text editor. 650. 1.20 2450. 1.17E-5 CONC25 28600 0. Microstran V9 18:Section & Material Libraries • 315 .17E-5 CONC40 36100 0.17E-5 F5 6900 0.17E-5 CONC32 32300 0. 1.0 1.17E-5 ALUMINIUM 65E3 0.The Material Library The material library may be edited by selecting the File > Configure > Edit Library command. On completion of editing you may elect to compile the source file.lib is compiled is shown below: 2 1 Materials Library N/mm2. .10E-5 CONC20 25500 0. degC 4 1.20 2450.33 2700. 1050.20 2450.0 1. 0. 0. 1.25 7850. F17 14000 0.20 2450. F11 10500 0. 1. 2. 1.17E-5 CONC50 40400 0. 0. 1st Edition $ Concrete props: Ref AS3600 $ Timber props: Ref AS1720.0 $ $ Steel props: Ref AISC DCT. The material property library text file from which the library file Matl.20 2450.
316 • 18:Section & Material Libraries Microstran V9 .
The design procedure automatically accesses the design data and analysis results for the selected load cases. The RC design options operate on standard Microstran models so that once you have analysed a structure you may proceed to determine the reinforcement for each member in accordance with the requirements of the design code. Initializing members assigns default design data that may be displayed or edited with the Design > Design Data command. If the design indicates different sections to the ones originally specified the model should be updated and the analysis repeated to take account of any resulting redistribution of member forces. Reinforced concrete design options for Microstran allow you to design reinforced concrete beams and columns. For convenience.. this data is saved automatically when you save the Microstran job (in the Job.19:RC Design & Detailing General RC design modules require the use of kN and meter units in the structure model. Once entered. based on the results of design computations. where "Job" is the job name). Section and reinforcement details may be changed as required. Microstran V9 19:RC Design & Detailing • 317 . section dimensions are in mm. and when you export to an archive file.msw file. Design options are available to AS 3600-1994 "Concrete Structures" and BS 8110:Part 1:1985 "Structural Use of Concrete". You must initialize all members to be designed and also select the design load cases before any design operations may be performed.
Beams are loaded so as to bend about the member z axis (see "Section Axes". The section X and Y axes are parallel to the member z and y axes respectively. Reinforcing bars are not bundled. members should extend from intersection point to intersection point without additional intermediate nodes. Limitations The following limitations apply to the reinforced concrete design module: • • • • The model must use units of kN and meters. below). The section axes may also be referred to as XX and YY.Detailing Option The reinforced concrete detailing option uses the results generated by the design module to generate a CAD drawing (in standard DXF format) with reinforcement details and bar lists for all beams and columns designed. SECTION AXES 318 • 19:RC Design & Detailing Microstran V9 . Columns are symmetrically reinforced with the same cover on each face. as illustrated in the accompanying diagram (see also "Coordinate Systems" on page 63). Section Axes The reinforced concrete design module uses "section" axes. For meaningful deflection computations.
the section type is set to that used in analysis. is specified with the File > Configure > Reinforced Concrete Design command. If you find the items on the sub-menu are disabled after selecting Design Data. Design Data DESIGN > DESIGN DATA On selecting the Design > Design Data > Input/Edit command select an initialized member so you can enter design data. Select the members you wish to initialize (see "Selecting Nodes and Members" on page 24). and have no member releases or rigid offsets. including the reinforced concrete design code. where appropriate. Default member design data. Assigns default design data to initialized members. Microstran V9 19:RC Design & Detailing • 319 .Initializing Design Members DESIGN > INITIALIZE DESIGN MEMBERS Initializing design members performs three functions: • • • Associates each initialized member with a specific design code. Linking of RC members controls detailing operations. select the Design > Initialize Design Members command. have the same section properties and orientation. Links members together into design members. Linked members will be detailed as a single "run" of members instead of individual beams or columns. By default. Linked members must be collinear.
For members initialized as reinforced concrete columns the first dialog box is displayed and for beams the second is displayed. DESIGN DATA – RC COLUMN 320 • 19:RC Design & Detailing Microstran V9 . CHOOSING THE DESIGN CODE The next step is to enter basic design data for the selected member in one of the dialog boxes shown below.In the first dialog box. Default data may be modified via options on the File > Configure menu. Additional pop-up help may be obtained for any item by clicking the button at the top of the dialog box and then clicking on the item. you choose the design code from those available in the list box. These are small pop-up windows that appear as the cursor passes over an item. Tool tips are provided for all items in the design dialog boxes.
and whether the design is to consider the torsion provisions of the design code. desired bar pattern and clear covers. The section of the defaults file that refers to AS 3600 is listed below.The data required for column design is the shape (rectangular or circular). T. widths of the supports at the ends of the beam.def file in the library folder. Default Values The default values for reinforced concrete design and detailing parameters are read from the Msrc. reinforcement data. If the beam is supported by columns. For unbraced columns designed to AS 3600. or L). which is ignored by the program. section dimensions. this value will normally be half the column width. top and bottom clear covers. the effective length. Microstran V9 19:RC Design & Detailing • 321 . There are different sections in the file for different design codes. and sway condition. the dimensions of the concrete section. DESIGN DATA – RC BEAM The data required for beam design is the beam shape (rectangular. you must also input the value of the storey moment magnifier δs. Note that "Support 1/2 width" is the distance from the beam end node to the face of the support. locations of the critical sections for shear. Each line in the file contains a keyword commencing in column 1 and one or more items of data. The dollar character "$" is used to indicate that the remainder of the line is a comment.
322 • 19:RC Design & Detailing Microstran V9 .0 $ f'c FSYC 400. for longitudinal bars DIATC 10.0 $ dist. no. 32. bottom bars CRITVL 1.0 $ dist. 8 0. 800.f for transverse reinforcement CVBEM 30. areas $ up to 15 sizes TSPAC 37. 110. reinf.0 $ fsy DIABC 16.Y=Yes N=No $ Default column shape .depth. $ clear cover to ties CSBLK RECT $ stress block . shear reinforcement NPLEG 1 $ no. start angle $ $ Default data for beams: $ FCB 25. 200. top bars DIABB 16.comment out whichever is not required: CSHAPE RECT 350. 10. 350. $ minimum dia. $ flange width. 1020. column . $ tee beam .0 $ effective length factors KY 1. 78. 300. beam . 3 3 $ rect. 350. 20. web width. $ trans. top bars MLBTM 2 $ max. section for shear=CRITVL*d from LH support CRITVR 1. 50. flange thickness CGRAD 20. grades (up to 5) SDIA 6. 40. 150. no.$ $ Concrete Defaults File MSRC. pairs of legs in shear reinf. 16. width $ BSHAPE TEE 500. 36.bx. bars.CEB/RECT KX 1. bottom bars FSYV 400. $ reinf. $ fsy for longitudinal reinforcement DIATB 12. 400. RSHEAR N $ shear flag .0 XSWAY Y $ sway about section X (member z) axis . 50. section for shear=CRITVR*d from RH support $ Default beam shape .0 $ minimum dia. $ minimum dia.0 $ circ. 8. $ rect. column .dia. 350. 450. layers. $ reinf. 32. 100. carries total shear $ N otherwise TORQUE Y $ design for torsion MLTOP 2 $ max. 24. $ concrete grades (up to 10) SGRAD 250. 75. no. Moving the "$" sign changes the default column or beam cross-section. by. 28. 310. 200. nx. 1200. diameters SAREA 28. $ fsy. 600.Y=Yes N=No YSWAY N $ sway about section Y (member y) axis . 450. $ dia. 12. ny $ CSHAPE CIRC 400. $ clear cover to shear reinforcement DSHEAR 10.5 50. 620.depth.. 120. $ reinf. $ diameter of ties CVCOL 35.DEF $ $ Default data for AS3600 $ RC_DATA AS3600 $ $ Default data for columns: $ FCC 32. 450. layers. $ standard spaces $ up to 15 spaces END Alternative CSHAPE and BSHAPE statements are preceded by the "$" character. $ f'c FSYB 400.comment out whichever is not required: BSHAPE RECT 450. 25.Y if reinf.
If load cases are not specified for deflection design. The rules for lists are set out in Chapter 15 – "Reports".Selecting Design Load Cases DESIGN > DESIGN LOAD CASES You must select the load cases to be considered in the reinforced concrete design. Sometimes. deflection checks are not performed. it might be more convenient to enter a list of load case numbers rather than selecting graphically. To do this. enter the list in the List edit box and click the Use List button. One or more load cases must be specified for strength design. SELECTING LOAD CASES Microstran V9 19:RC Design & Detailing • 323 . All load case titles are shown in a list box and you may select any of these by clicking on them.
You also specify whether an existing design report is to be overwritten or added to (design reports are automatically deleted when you close a job so. the design data dialog box will be displayed for the current member so you can change the section dimensions as required. If the interactive design mode is chosen you have an opportunity to review the design. Select the members to be designed (see "Selecting Nodes and Members" on page 24). 324 • 19:RC Design & Detailing Microstran V9 . CHOOSING DESIGN PROCEDURE The reinforcement requirements are determined for each of the selected members. there is no existing design report).The Design Process DESIGN > REINFORCED CONCRETE The Design > Reinforced Concrete command initiates the member design process. The dialog box below lets you choose whether the design procedure is to be automatic or interactive. The interactive design procedure is discussed in detail below. or if there are no bars large enough. initially. If for any member excessive reinforcement would be required.
for example. Clicking the Revise button allows you to change the column design data and repeat the design. CHANGING BAR ARRANGEMENT Microstran V9 19:RC Design & Detailing • 325 . INTERACTIVE DISPLAY – COLUMN DESIGN If the design details are satisfactory click the Continue button to proceed to the next member selected for design. You may click any of these buttons to change the bar arrangement at the corresponding location in the beam. REINFORCEMENT LAYOUT The bar arrangement is shown on a button at each of 6 locations in the beam. denotes 11 × Y16 bars in 2 layers. If you do so. together with the area of steel required by the design.Designing Columns When you select the interactive design mode the results of the current design are displayed. The notation "11-Y16 2L". the cross-sectional area of the selected arrangement is displayed. Designing Beams When you select the interactive design mode the reinforcement layout selected for the beam is displayed.
Clicking the Revise button allows you to change the column design data and repeat the design.If you are going to use the detailing option you should ensure that a single bar size is used at all bottom locations in any design member. INTERACTIVE DISPLAY – BEAM DESIGN If the design details are satisfactory click the Continue button to proceed to the next member selected for design. 326 • 19:RC Design & Detailing Microstran V9 . You may save an RC design report file by dragging it to another folder using Windows Explorer. RC design results are not saved when you save a job and the RC design report file is automatically deleted (if it exists) when the job is closed. The RC design report file is created in the data folder and it is named Job. The design report may be previewed with the File > Print Preview command and it may be printed with the File > Print File command. Design results are automatically written to a design report file during reinforced concrete design. where "Job" is the job name. Obtaining Design Results After designing members the design results may be displayed or reported in a number of ways: Use the Query > Design Member command to show the design status in the output window for any selected member. The RC design report may be recreated by repeating the design procedure. Note that there are extensive facilities for formatting the design report using the File > Page Setup command.p5. The results of the current design are then displayed.
The following general assumptions are made in computing the failure load: • • • The strain distribution in both concrete and reinforcement is linear across the section. Capacities are computed using the area and coordinates of each bar and not by using an "equivalent" steel area. up to a maximum of 20 mm. It does not use empirical interaction formulae in conjunction with uniaxial capacities. If the column strength is inadequate at any point larger bars will be selected and bar positions adjusted to maintain cover before checking proceeds.8. The ultimate strain in the concrete is 0. depending on the setting of the stress block flag in the default data file. the moment magnifier is taken as the maximum of δs (entered by the designer) and the computed value. plane sections remain plane. On completion of the bar area calculations a bar size that satisfies the most critical load condition is selected. 3.002 when the neutral axis is at infinity. the positions of the reinforcing bars are adjusted to reflect the largest size so far determined. The stresses in the concrete are described by the simplified stress block of BS 8110 Fig. The ultimate strain in the concrete is 0. The maximum eccentricity is that at which the axial force causes the section to reach its effective strength when applied at an angle Microstran V9 19:RC Design & Detailing • 327 . Intermediate values are obtained by linear interpolation. If the column is unbraced.0035. is also applied.Column Design Computations Microstran checks the column section with the minimum reinforcement size in the specified pattern along the full length of member. For AS 3600: Bending moments are magnified if the column is slender.e. General A rigorous method is used to calculate biaxial bending effects. δb. As the computations proceed.003 when the neutral axis is within the section and 0. A minimum design moment due to the axial force acting at an eccentricity of 0. For BS 8110: Additional moments induced by lateral deflection of the column at the ultimate limit state are computed in accordance with Clause 3. The stresses in the concrete are described by either the CEB curve or a rectangular stress block. The tensile strength of the concrete is neglected. The reinforcement is perfectly elastic-plastic with equal tensile and compressive yield stresses.3. The minimum moment of 0. i. The position of the neutral axis (as an offset and angle from the plastic centroid) and the maximum eccentricity are then determined for each load condition.05D × N* is applied.05 times the dimension of the column in the plane of bending.3.
In interactive mode. Torsional steel requirements (longitudinal reinforcement) are computed assuming a "rational" layout of the flexural reinforcement. This procedure is not accurate if the support width is large – in this case. Beam Design Computations Longitudinal reinforcement is determined from bending moments about the section X axis at the face of the supports.I cr ) ⎛ M cr ⎞ ⎜ ⎟ ⎜ ⎟ ⎝ Ms ⎠ 3 The lowest value of Ief is then used in all deflection calculations. Transverse reinforcement is computed for each load case in turn and the minimum bar spacing at each point is used to select an arrangement of links based on a set of preferred spacings.consistent with the ratio of the moments (adjusted for slenderness) about the section X and Y axes. Deflections are computed by scaling the analysis deflections by the ratio of the stiffness (EI) used in the analysis to that computed for the selected section. Compression reinforcement is added as needed. you may accept the design or revise the section dimensions and reinforcement patterns. Anchorage of shear reinforcement is not checked. For cantilever ends – assumed for nodes with no support in the direction of the member y axis and no connected members 328 • 19:RC Design & Detailing Microstran V9 . In interactive mode. Axial forces. Effective inertias are computed for all cases designated for deflection from Branson's formula: I ef = I cr + (I . If clearance is inadequate. you may modify the longitudinal reinforcement selected by the program to match that in adjacent beams or to control deflections. Member forces at the face of the support are approximated by interpolation. the structural model should include rigid member offsets to obtain accurate member forces. Bending moments are not redistributed. a design report for the member is added to the design report file. The difference between the load and maximum eccentricities gives a measure of the excess capacity of the section. and moments about the section Y axis. are not considered in the computation of longitudinal reinforcement for beams. On acceptance. If these actions are significant you will need to carry out additional manual calculations. The excess is due to the difference between the computed and selected bar areas. The deflections reported are the maximum displacements in the member y direction measured from the displaced position of the chord joining the end nodes of the beam. effective depths are adjusted and steel areas are recomputed. Bar patterns are selected at the ends and centre of the beam and checked for clearance.
cracked and effective inertias and the ratios of compression reinforcement to tensile reinforcement are written to the report. When the design is accepted a report for the member is added to the design report file. In interactive mode you have the option of revising the member design. defined in AS 3600 Clause 8. The computed values of gross. Microstran V9 19:RC Design & Detailing • 329 . Immediate deflection and additional long-term deflection (due to creep and shrinkage) are reported for each load case selected for deflection computations. The additional long term deflection is computed by multiplying the short term deflection by the multiplier kcs.3.3 as a function of Asc/Ast.– the tip displacement is reported relative to the displacement of the fixed end.5.
400 2 SHAP 0.350 1.000 0.0000 3.500 0.0000 0. applied loads and bending moment for the design load cases.000 -40.5WU 1 1.25G + 0.250 2 0. * TEST FRAME FOR RC DESIGN * SINGLE BAY RECTANGULAR PORTAL FRAME * * VERS 4 TYPE 3 VERT 2 UNIT 1 m kN T C NODE NODE NODE NODE MEMB MEMB MEMB PROP PROP 1 2 3 6 1 2 3 0.4Q + 1.000 2 0.350 1.000 0.900 2.000 -25.0000 0.00 400x350 600x350 MATL CASE NDLD NDLD MBLD CASE MBLD CASE MBLD MBLD MBLD CASE COMB COMB CASE COMB COMB CASE COMB COMB COMB END 1 3.000 0.600 RECT COLUMN 0.000 GL -35.0000 0.0000 D D D 1 2 1 0.000 0.500 6 1.RC Design Example A small rectangular portal frame has been used as the design example.230E+07 2.000 LO LO LO -3.450E+00 1.0000 1 1 1 111111 001110 001110 111111 000000 000000 000000 000000 000000 000000 1 SHAP 0.000 0.5Q 1 1.250 2 1.000 -40.600 -4.000 0.400 3 1.0000 1 2 6 2 3 3 0.700 5 1.25G + 1.000 0.7Q 1 1.0000 7.300 330 • 19:RC Design & Detailing Microstran V9 .5000 0. The archive file defining the job is shown below together with plots of the structure geometry.000E-01 2.0000 7.170E-05 1 DEAD LOAD 2 0.5000 3.000 3 0.00 RECT RAFTER 0.0000 0.000 2 UNIF FY GL 2 LIVE LOAD 2 UNIF FY 3 WIND LOAD 1 UNIF FY 2 UNIF FY 3 UNIF FY 4 G + 0.
DESIGN EXAMPLE DESIGN EXAMPLE – SECTIONS DESIGN EXAMPLE – BENDING MOMENT Microstran V9 19:RC Design & Detailing • 331 .
000 Magn.94 Ref.12 -184.8 m mm mm kNm m mm mm kNm Case 5 6 á.4Q + 1.571% (Rectangular stress block) == R C B E A M D E S I G N R E P O R T == MEMBER: 2 (Design to AS 3600) Length: 7.000 234 -. *** Selected: 8-Y24 .09 0.: Shape: (Design to AS 3600) 1 30 MPa 12 mm RECT Node "B": fsy: Cover: Width: Depth: Reinforcement: Pattern: kx: Lex: rx: Braced: Eff.00 Magn. "x" dim.: 12 mm Top cover: Support half-width Left: f'c: 32 MPa fsy: N: Vy: Vx: T: My: Mx: -79.0 m Node "A": 2 Node "B": 3 Shape: RECT Web width: Stirrup dia.58 79.dy Ncy kmy 343 -.short column -1.00 -184. node/axis: -X MPa Q/G: 0.5Q 1. cover: 40 mm 225 mm Right: 225 mm 400 MPa fsy.7Q - R C D E F L E C T I O N C H E C K == == R C C O L U M N D E S I G N R E P O R T == MEMBER: 1 Node "A": f'c: Tie dia. (|| member "z") mm sect.5 120 Yes 282 189.104 1.00 -184.Mubx: 2 400 40 350 400 3 3 Ref.5 105 Yes 242 158. node/axis: Y 350 mm Depth: 600 mm 40 mm Btm.00 0.x 1.00 0.87 kN kN kN kNm kNm kNm ë.94 M*y kNm 0.2 Length: 3.02 kN kN kN kNm kNm kNm (Compression -ve) (Shear) (Shear) (Torque) (Moment) (Moment) Member Force Ranges: (Analysis) 332 • 19:RC Design & Detailing Microstran V9 .00 0.by N* á.43 0.000 3645 1.12 0.25G + 1.00 3.bx á.dy ë.09 -293.068 Member Force Ranges: (Analysis) (Compression -ve) (Shear) (Shear) (Torque) (Moment) (Moment) Maximum Load Conditions: Case Pt.3) = ád for YY bending = Braced column moment magnifier for XX bending = Braced column moment magnifier for YY bending N: Vy: Vx: T: My: Mx: -343.00 328.00 mm mm sect.00 3.12 0.25G + 0.00 0.short column -1.000 = ád for XX bending (10.y 1.12 37. (|| member "y") bars each face || member "z" axis bars each face || member "y" axis ky: Ley: ry: Braced: Eff.00 0.dx Ncx kmx ë.5 m 1.dx á.f: 400 MPa -56.Muby: 1.by 1.104 Magnified moment resultant is 0.Reinforcement percentage: 2.Design Example – Report File == L O A D Case Type 5 C 6 C C A S E S R C S T R E N G T H D E S I G N == Title 1.970 of ultimate moment resultant for an axial load of 343. N* M*x kN kNm 5 21 343. depth: í.00 0.bx ë.94 -233.00 0.4.5WU == L O A D Case Type 4 C C A S E S Title G + 0. "y" dim.00 0.33 293.000 3645 1.00 91.12 kN. depth: í.
2 kN Microstran V9 19:RC Design & Detailing • 333 . 156. 117. 0. 79.329% 328.168% End "B" 141. 156. 0. 79. 79. 117. 156. 79. 147.168% Code minimum strength (8. 0.4.00 0. 0. T* kNm 0. 117.04 4.04 77. 0. (pos. /-Bending-/ ku M* 0. 79. 0 0 0. 0. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 Case 5 5 5 5 5 5 5 5 5 5 6 5 5 5 5 5 5 5 5 5 5 49.05 87. /-Bending-/ ku M* 0.max: Pt. 0.19 308. 117. 0. 0. Shear at critical sections .00 0. 0. 229.08 141.00 0.00 0.): Area (mm^2): Percentage: 0. 156. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 Flex. 0.Dia: 12 mm Grade: 400 MPa Concrete carries part of shear. 79. 88. 117.04 1. 56. 79. 0 0 0.00 0. 0. 156. 117. 0. 0. 0.00 0. 0. 229.00 0.00 0.15 246.17 282. 1. 0 0 0. 156. 156. 156. 0. 0. 0 0 0. 0 0 0. 0. 79.00 0.4 7-Y20 2L 2170 1.168% Mxx (neg. 0.4 7-Y20 2L 2170 1. Pos. 79. 0. N* kN 79.20 328. 0. 0 0 0.00*d from face of left support. 0 0 0. 176. 0.20 323. 79. Critical sections at: 1.00 0.15 246.00*d from face of right support.12 200. 29. 0.Longitudinal Design -End "A" 141. 229.1. 0. 229.00 0.00 0. 0. 0. 79. 0. 0. 79. 0.05 87. 79. 0. 0 0 0.1): M*min. 0. (neg. 0. 0. 0 0 0. 404. /--Required-/ Astop Asbtm 848 0 519 0 404 0 0 460 0 875 0 1238 0 1544 0 1788 0 1966 0 2075 0 2111 0 2075 0 1966 0 1788 0 1544 0 1238 0 875 0 460 404 0 519 0 848 0 /----Torsion----/ T* Astop Asbtm 0. 0.): Area (mm^2): Percentage: Mxx (pos. 0 0 0.00 0. 0. 0. 0 0 0. 0.00 0.08 143.): Reinf. 79.08 141. 0. mm^2 404. 156. 0. 0. 205.12 200. 0 0 0.1 3-Y20 1L 930 0. 0 0 0.04 77.0 2-Y20 1L 620 0. 0 0 0. 147.00 0. 0. 0. 79.neg: 68. 0.17 282. 156.9 kNm 188. 0. mm^2 Pt. 0 0 0. 0 0 0. 0. 0. 79.1 3-Y20 1L 930 0. 117. 59. 79. 79. 0. 156.08 143.00 0. 229.00 0. 156. 1. 0. 0. 0.pos: 68. 176. 59.2 kNm V* kN 229. 0.19 308. 88.): Reinf.00 0. 205. 0. 0. 79.00 0.Left: -229.4 kNm As: M*min. 156.Transverse Design -2 Legged stirrups . 0.494% 143.-.494% 143.20 323. 0. 0 0 0. 0 0 0.00 0. 0 0 0. s mm 300 300 300 300 450 450 450 450 450 99999 99999 99999 450 450 450 450 450 300 300 300 300 229.0 7-Y20 2L 2170 1. 29. Ast mm^2 930 930 930 2170 2170 2170 2170 2170 2170 2170 2170 2170 2170 2170 2170 2170 2170 2170 930 930 930 Vuc kN 117. 156. 156. 0.2 kN Right: Tuc: Tu. 0 0 /--Supplied-/ Astop Asbtm 930 2170 930 2170 930 2170 930 2170 930 2170 620 2170 620 2170 620 2170 620 2170 620 2170 620 2170 620 2170 620 2170 620 2170 620 2170 620 2170 930 2170 930 2170 930 2170 930 2170 930 2170 -.00 0.4 kNm As: Neg. 0. 0. 0. 0 0 0.
333 kNm kNm mm^4 mm^4 mm^4 mm Case 4 /---.333 Effective Inertia Ieff: 2. Beams are parallel to a global axis and columns are vertical.3 Mcr: 71.Selected Stirrup Spacings: Face of support. Members to be detailed in a single run must have been initialized as linked.755E+09 168. mm. mm. Detailing generally follows standard industry practice as described in Standard Method of Detailing Structural Concrete (Institution of Structural Engineers. mm -18. -10. mm.3 71. End "B" -. the "A" node must be at the bottom.relative to displaced position of end nodes.3 Igr: 6.relative tip deflection.712E+09 110. End "A" @ 75 @300 @450 @250 @450 @300 @ 75 Face of support.300E+09 Icr: 1.336E+09 2. Limitations The following limitations apply to the reinforced concrete detailing module: • • • • The Microstran model has either the Y or the Z global axis vertical.3 6.0 Centre 193.286 Right -109. Cantilevers . and the Reinforcement Detailing Handbook (Concrete Institute of Australia).e.9 71.300E+09 2. Columns must have their local x axis up.300E+09 1. mm L/defl.336E+09 Ieff: 2. mm.9 0. After a reinforced concrete design session you may select the Design > RC Detailing command and the detailing module will automatically produce a CAD transfer file containing the reinforcement layout for all beams and columns just designed. Long Term Defl.4 2.570E+09 2.3 6. i.4 Asc/Ast: 2. Operation Reinforced concrete details are generated by selecting the Design > RC Detailing command after reinforced concrete design has been 334 • 19:RC Design & Detailing Microstran V9 . mm. UK). Load case giving minimum Ieff: Case 4 Left M: -109. Deflections are measured in local "y" direction.Immediate ---/ Defl.9 643 Reinforced Concrete Detailing Option The integrated reinforced concrete detailing option may be used with any of the Microstran reinforced concrete design modules. mm.Deflections -- -> mm mm mm mm mm mm mm -> for for for for for for for 75 1200 1800 250 1350 1800 75 mm.712E+09 NA depth: 110. Beams .734E+09 mm^4 Addn.
beams are drawn so that grid lines are aligned vertically.successfully completed for one or more members. Columns are drawn starting to the right of the beams. including bar lengths. Beams are drawn on the left.dxf.def file and the styles to be used for text and dimensions are specified in a header DXF file. Input The reinforced concrete detailing module obtains both geometric and design data directly from Microstran. Reinforcement details are generated in a standard format DXF file (AutoCAD R12 format) named Job. The resulting CAD drawing contains all beam and column details for the last design session. where "Job" is the current job name. either looking in the -Z or -X directions for vertical Y axis. This file may be read into most CAD programs (e. Only one main bar is drawn in the elevation but all are shown in the cross-section. starting at the bottom of the drawing. All column elevations are shown from the same direction. These details may then be transferred as required to reinforcement detail sheets. An elevation is shown for each column with a mid-height cross-section shown on the right for each storey. A reinforcement schedule is generated for each run of beams with bar data. or the -Y or -X directions for vertical Z axis. summarized in tabular form. A reinforcement schedule is also shown for each run of columns. Beams framing into the column are shown to scale in elevation and section. using the DXFIN command in AutoCAD). CAD drawing defaults are defined in the Msrc. Where possible. Warning messages (on a separate layer) will appear on the drawing when known unresolved situations occur. Drawing Layout The CAD drawing is full-size in millimeters with cross-sections drawn at double scale. It is intended that the details produced will be reviewed by the designer with any inconsistencies being remedied as required. Cross-sections are shown below the beam for each mid-span and support location.g. Microstran V9 19:RC Design & Detailing • 335 .
The specified text style is used for all the drawing except the reinforcement schedules. Each line in the file contains a keyword followed by a parameter value. Both text styles must exist in the header DXF and the specified style must • • • 336 • 19:RC Design & Detailing Microstran V9 . Concrete outlines are drawn as polylines of 5 units width.beams Extension of column centre-line above beam Extension of column centre-line below beam Start distance for dimensioning above beam Start distance for dimensioning below beam Length of bar end bend Lateral offset of bar end bend Horizontal clearance . displaying the Msrc. a warning message is plotted in the messages layer.00 GRADE_SEP 300 GRADE_BELOW R GRADE_ABOVE Y COL_ELEV 1 LINKS_DIAMOND 1 END (AS) $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ Name of header DXF . Any line type.DXF LAYER_CL CENTRE LAYER_CONC OUTLINE LAYER_REINF REINF LAYER_TEXT TEXT LAYER_DIMS DIMENS LAYER_LINKDIMS LINKDIMENS LAYER_SUPPS SUPPORTS LAYER_MSG MESSAGES TEXT_STYLE STANDARD BEAM_HCLEAR 3500 BEAM_VCLEAR 10000 COL_CLEXTABOVE 920 COL_CLEXTBELOW 780 BEAM_DIMABOVE 1600 BEAM_DIMBELOW 800 BEND_LENGTH 100 BEND_OFFSET 25 COL_HCLEAR 6000 COL_VCLEAR 1000 XSECT_FACT 2. Anything following the dollar symbol is a comment.columns Scale factor for plotting cross-sections Transition steel grade Bar type for steel grade below transition grade Bar type for steel grade above transition grade Column elevation: 1=Normal 2=Rotated Use diamond-shaped links: 1=Yes 0=No Note that: • • • All layers specified in the parameter file must be defined in the header DXF.don't change Name of layer for centre-lines Name of layer for concrete outline Name of layer for reinforcement Name of layer for text Name of layer for dimensions Name of layer for link dimension lines Name of layer for supports Name of layer for messages Name of text style Horizontal clearance . Supports will be shown if they exist where columns do not. Each reinforcing bar is drawn to scale as a polyline with a width equal to the bar size. $ $ Default data for detailing $ DETAIL_DATA AS3600 DXF_HEAD HEADER. This command initiates Microstran's text editor.columns Vertical clearance .def file. The dimensioning style is determined by the variables set in the header DXF.CAD Drawing Defaults The default values used by the program may be changed by selecting the File > Configure > RC Design > Default RC Data command. for example. which are drawn in style MONO. Reinforcement schedules are drawn in the text layer. Where a problem has been encountered in detailing.beams Vertical clearance . may be changed by changing the line type used for the corresponding layer. It defines drawing parameters such as layer names and configurable detailing parameters. The part of the file that affects detailing is shown below.
dxf that is located in the library folder. or 12. It may be altered as required by editing the file directly or by reading it into a CAD system then changing the settings and saving the file in the correct format. The header DXF is.def file should exist in the header DXF. 11. If arrowheads are required on dimension lines instead of 45° tick marks. The transition steel grade is the grade above which any reinforcement will be assumed to be high-yield deformed bar. The Header. in effect. text style and height. The start distances for dimensioning are the distances in drawing units of the topmost dimension away from the beam profile.not be MONO. dimension style. Items that may be changed include layer names.dxf file distributed with the detailing module is compatible with AutoCAD Release 10. The length and lateral offset of the bar end bend define the size in drawing units of the artificial bend shown at the ends of horizontal bars to distinguish them from other bars in the same layer. the colours or line types of the various layers may be changed in this way. At and below this grade. To avoid the possibility of conflicts between the prototype drawing and the header DXF. and also AutoCAD LT. The same clearance is used between the rightmost beam schedule and the first column detail. All layers referenced in the Msrc. It is read by the detailing program. MONO should be defined as a monospaced font so that the columns of text in the schedule are properly aligned. This is a file called Header. the dimensioning variables. colours. reinforcement will be assumed to be mild steel plain bar. a prototype drawing to which the reinforced concrete details are added. making changes. usually "T" or "Y" for high-yield bars and "R" for plain bars. Horizontal and vertical clearances are also specified for columns. it is recommended that your CAD program is configured for no prototype drawing. and then outputting it (DXFOUT). • The horizontal clearance is the distance in drawing units between the end of a run of beams and the corresponding reinforcement schedule. and line types. Several style features of the output drawing may be changed automatically by editing this file. the variable DIMTSZ must be set to zero. The column centre-line extensions above and below the beam are the distances in drawing units that the centre-line extends beyond the beam profile. The vertical clearance is the distance in drawing units between each run of beams. interpreted as required. This file may be changed as required. and written to the output DXF. The header file must Microstran V9 19:RC Design & Detailing • 337 . either by editing it directly or by bringing it into the CAD program (DXFIN). For example. The bar types for steel grade are alphabetical codes prefixed to bar sizes to indicate bar grade. and so on. • • • • The Header DXF Drafting defaults such as line types. and text size are specified in the header DXF.
If these are altered. At the top of a run of columns. below the structural floor level. Splice bars in the bottom of beams at supports are terminated 35 bar diameters from the face of the column or support. you should be aware that the deflection calculations in the design report may no longer be valid. It is emphasized that the designer and detailer are responsible for refining or correcting the automatically produced details. The specified style must not be MONO. in that order.contain the text style referred to in the parameter file and MONO. relieve the designer and detailer of much of the routine work. identical bars in different layers are allocated different numbers. In some cases. the main bars are arbitrarily bent inwards. The bottom steel in each beam is constant throughout. Some steel may be saved by specifying cut-off points towards the ends of the span. however. If you do this. At column/beam intersections. these bars should be bent into adjacent • • • • • • 338 • 19:RC Design & Detailing Microstran V9 . It can. in a 90° bend of 8 bar diameters. Beam cross-sections do not show the lapping of the cage steel with bars that are continuous through supports. The following dimension variables defined in the header DXF are interpreted by the detailing program. No more than three pairs of legs are permitted in the current version of the software. no consideration is given to the possibility of interference between beam and column reinforcing bars (or the bars of intersecting beams). In beams. the detail drawing will be affected correspondingly. DIMASZ DIMDLE DIMDLI DIMEXE DIMEXO DIMTSZ DIMTVP DIMTXT Arrow size Dimension line extension Increment between continuing dimension lines Extension distance for extension lines Offset distance for extension lines Tick size (arrows if zero) Text vertical position Text size Detailing Features Automatic design and detailing of beams and columns is not a complete substitute for the normal procedures. Some areas where attention may be required are: • Link sets in beams are identical throughout the length of the beam (but the spacing may vary). allowing them to concentrate on the aspects that are impossible or difficult for a program such as this to handle.
A parameter may be set in the Msrc. • • • • Starter bars projecting into columns above are terminated 30 bar diameters above the kicker (assumed to be 75 mm high). Microstran V9 19:RC Design & Detailing • 339 . Minimum joggle length in column bars is 300 mm or 10 bar diameters.beams. Diamond-shaped ties may be used instead of single links where there is a central bar in each face of a rectangular column and the maximum included angle does not exceed 135°. There is a 75 mm clearance above starter bars to the start of a joggle. The designer and detailer must consider what is to be done here. Design codes may permit alternate outer vertical bars in columns to be unsupported by links as long as the spacing does not exceed 150 mm. • Detailing Example A small rectangular portal frame has been used as the detailing example. The archive file defining the job is shown in this chapter (see "RC Design Example" on page 330). In the current version of the software all vertical bars are restrained by links. whichever is the greater.def file if you do not want diamond-shaped links.
DETAILING EXAMPLE 340 • 19:RC Design & Detailing Microstran V9 .
Examples have been chosen to include several common problem areas in modelling. Many common structures can be described easily with Standard Structures Input (see Chapter 8). Microstran V9 20:Examples • 341 . A wide variation of formats is possible by modifying the default values in the Page Setup dialog box. Report presentations have been varied to demonstrate different features of the report generator. For all examples the archive file is presented as a complete record of the input data. especially node restraint conditions and member releases.20:Examples The examples in this chapter are presented to illustrate specific features of Microstran. It is possible to enter data by creating the archive file but it is not usually the most convenient input method.
067 300.000 -.000E+00 1 PRIS SECT_1 20.0000 . MATL CASE MBLD MBLD MBLD END 1 3. loads.0000 D D 1 1 . This is typical of the graphical output that may be produced by Microstran.0000 .0000 111110 .0000 001110 .0000 6000.000 180. Archive File * SPRING SUPPORTED CONTINUOUS BEAM * UNITS: INCHES KIPS .000E+01 0.0000 .000E+04 3. This is reproduced in the following pages. member forces.0000 .000E+00 0.000E-01 0.000E+00 1 EXAMPLE APPLIED LOAD 1 CONC FY GL LE 1 TRAP FY GL LE 2 UNIF FY GL -6.00 .0000 300. and displacements at the nodes.BEAUFAIT ET AL EX 5-22 * * VERS 4 TYPE 3 VERT 2 UNIT 5 in kip k/g F NODE NODE NODE MEMB MEMB SPRN PROP 1 2 3 1 2 .000 -.0000 . EXAMPLE 1 – CONTINUOUS BEAM A full analysis report has been generated for this structure using the default settings to provide tables of all structure data.0000 011110 1 1 000000 000000 000000 000000 2 0.000E+00 1.000 342 • 20:Examples Microstran V9 .0000 660.000E+00 0.067 180.000E+00 0.067 -.Example 1 – Continuous Beam Example 1 is a two-span continuous beam with a central spring support. The structure and shear force diagram are shown in the accompanying output.000E+00 0.0000 1 2 2 3 .
Microstran V9 20:Examples • 343 .
344 • 20:Examples Microstran V9 .
The report shows forces and displacements at 1/5th points along each member for load case 7. 1 and 5. no rotational displacement would be computed at the base of each column. The structure and bending moment diagram are shown in the accompanying output. Note that if this were done. Microstran V9 20:Examples • 345 .Example 2 – Portal Frame Example 2 is a portal frame in the XY plane. The columns are pinned at the base nodes by allowing Z rotations in the restraint codes for the support nodes. Up to 40 segments per member may be selected for the tabulation of forces and displacements along members. Note that you may obtain results along the length of the members without having to use additional nodes. EXAMPLE 2 – PORTAL FRAME Pinned bases could also have been modelled by making the support nodes fully fixed (restraint code 111111) and setting the z moment releases at the lower ends of members 1 and 4 (the release codes would then have been 000001 000000 and 000000 000001 respectively).
Archive File
* PORTAL FRAME * * * VERS 4 TYPE 3 VERT 2 UNIT 1 m kN NODE NODE NODE NODE NODE MEMB MEMB MEMB MEMB PROP PROP 1 2 3 4 5 1 2 3 4
.0000 .0000 12.0000 24.0000 24.0000 1 2 3 4
1 LIBR Asw.lib 1.6000E-02 .0000 2 LIBR Asw.lib 1.1800E-02 .0000
-4.000 -4.000
3.500 -2.500 1.500 1.000
346 • 20:Examples
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Example 3 – Space Truss
Example 3 is the top section of a high communications tower. It is modelled as a space truss (i.e. all rotational DOF deleted).
A common problem with this type of structure is the presence of coplanar nodes. Coplanar nodes have no out-of-plane stiffness because all attached members lie in a plane. Coplanar nodes will give rise to zero stiffness errors during the analysis or a large condition number, with extremely large displacements for the unrestrained DOF. In this example, a number of "redundant" members have been added to the
Microstran V9 20:Examples • 349
structure to provide out-of-plane support to nodes that would otherwise have been coplanar. A coplanar node may also be removed by deleting the DOF normal to the plane (if the plane is normal to a global axis) or by restraining the node with weak springs. The structure is shown in the accompanying Microstran graphical output. Note in the rendered view that the legs of the tower are oriented with the corners of the angles outwards. The section orientation codes can be seen on some MEMB lines of the archive file. These are required only for detailing – the analysis is not affected by the orientation of the section. The report shows the analysis results (for a range of nodes and members) for Case 3 , the combination load case. Archive File
* SPACE TRUSS EXAMPLE * TAKEN FROM TOWER 40HBJ101 * * VERS 4 TYPE 4 VERT 2 UNIT 1 m kN t C NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB 261 262 263 264 265 266 267 268 269 270 271 272 701 702 703 704 705 706 707 708 66 67 133 134 200 201 267 268 578 579 580 581 582 583 584 585 608 609 610 611 612 613 614 615 638 639 640 641 642 643 644 645 -1.0000 1.0000 1.0000 -1.0000 -1.0000 1.0000 1.0000 -1.0000 -1.0000 1.0000 1.0000 -1.0000 .0000 1.0000 .0000 -1.0000 .0000 1.0000 .0000 -1.0000 261 265 262 266 263 267 264 268 261 701 701 701 265 705 269 705 262 702 702 702 266 267 270 706 263 703 703 703 267 268 271 707 265 269 266 270 267 271 268 272 701 262 265 266 705 266 705 270 702 263 266 267 706 706 706 271 703 264 267 268 707 707 707 272 107.0000 107.0000 107.0000 107.0000 108.5000 108.5000 108.5000 108.5000 110.0000 110.0000 110.0000 110.0000 107.0000 107.0000 107.0000 107.0000 110.0000 110.0000 110.0000 110.0000 X X X X X X X X Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y Y 4 4 4 4 4 4 4 4 7 7 8 8 8 8 7 7 7 7 8 8 8 8 7 7 7 7 8 8 8 8 7 7 1.0000 1.0000 -1.0000 -1.0000 1.0000 1.0000 -1.0000 -1.0000 1.0000 1.0000 -1.0000 -1.0000 1.0000 .0000 -1.0000 .0000 1.0000 .0000 -1.0000 .0000 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 111111 111111 111111 111111 000111 000111 000111 000111 000111 000111 000111 000111 111111 111111 111111 111111 000111 000111 000111 000111 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000
01 01 11 11 10 10 10 10
11 11 10 10
11 11 10 10
11 11
350 • 20:Examples
Microstran V9
668 669 670 671 672 673 674 675 798 799 800 801 976 977 978 979 980 981
264 704 704 704 268 265 272 708 705 705 707 707 701 702 703 704 702 706
704 261 268 265 708 708 708 269 708 706 708 706 702 703 704 701 704 708
7 7 8 8 8 8 7 7 7 7 7 7 8 8 8 8 8 8
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
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10 10
11 11
4 LIBR Asw 1.8100E-03 .0000 7 LIBR Asw 8.6700E-04 .0000 8 LIBR Asw 7.4800E-04 .0000
.000 .000 .000 .000 .000 .000 .000 .000
.000 .000 .000 .000 .000 .000 .000 .000
.000 .000 .000 .000 .000 .000 .000 .000
.000 .000 .000 .000 .000 .000 .000 .000
-1.079 -1.079
.000 .000
.000 .000
.000 .000
.000 .000
Microstran V9
20:Examples • 351
352 • 20:Examples
Microstran V9
Microstran V9 20:Examples • 353 .
the analysis requires 4 iterations. Essentially identical results are obtained with 2 iterations if the node coordinate update check box is cleared. EXAMPLE 4 – NON-LINEAR ANALYSIS 354 • 20:Examples Microstran V9 .Example 4 – Non-Linear Analysis Example 4 demonstrates a non-linear analysis of a two-storey plane frame. The report shows the analysis results. Note that the settings of the analysis flags are shown on the report. With node coordinate update and axial force effects both in effect.
000 .0000 310UB40.0000 D D D D D D 10 11 21 22 21 22 .0900E-07 7.0000 5.0000 .2800E-05 5.0000 .0000 150UC30.4 .lib 5.8600E-03 .000 .0000 .0000 .Archive File * AISC WORKED EXAMPLES 4.2700E-08 Y 3.6400E-05 3.6200E-06 1.0600E-06 2.0000 .000 .0000 21 LIBR Asw.6500E-06 8.000 .0000 200UB25.000 .0000 200UC52.0 .2300E-03 .000 -32.5700E-07 Y 6.lib 3.000 .7700E-05 5.lib 3.000 -64.000 21 8.0000 .0000 10.000E+08 2.0000 11 21 1 11 2 12 12 22 11 21 12 22 .000 12 .2500E-07 Y 1.000 Microstran V9 20:Examples • 355 .000 .500 .6600E-03 .000 22 .000 .0000 10.lib 6.080E-05 1 FACTORED LOADS 11 16.0000 22 LIBR Asw.000 .3600E-05 1.2100E-03 .000E-01 7.0000 Y 1.000 .000 -32.0000 11 LIBR Asw.2 .000 .000 .0000 10.000 .5 * * * VERS 4 TYPE 3 VERT 2 UNIT 1 m kN t C NODE NODE NODE NODE NODE NODE MEMB MEMB MEMB MEMB MEMB MEMB PROP PROP PROP PROP 1 2 11 12 21 22 1 11 21 22 31 32 .0000 .000 .0000 5.7600E-05 MATL CASE NDLD NDLD NDLD NDLD MBLD MBLD END 1 2.850E+00 1.4 .500 .000 -16.0000 10.000 1 CONC FY GL FR 11 CONC FY GL FR .000 -16.000 -32.0000 10.000 .0000 .0000 1 1 1 1 1 1 111110 111110 001110 001110 001110 001110 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 10 LIBR Asw.
356 • 20:Examples Microstran V9 .
Microstran V9 20:Examples • 357 .
Example 5 – Elastic Critical Load Analysis Example 5 demonstrates an elastic critical load analysis of a two-storey plane frame. The accompanying diagram shows the first buckling mode shape superimposed on a rendered view of the structure. The report shows the structure geometry and the table of effective lengths. EXAMPLE 5 ELASTIC CRITICAL LOAD ANALYSIS 358 • 20:Examples Microstran V9 .
0000 .000E+00 2 VERTICAL AND HORIZONTAL LOADING 11 10.6100E-06 1.0000 20.4700E-05 MATL CASE NDLD NDLD END 1 2.000E+08 2.0000 .0000 10.8800E-02 .8800E-02 .0000 10.0000 10.0000 .0000 2 LIBR Asw.0000 10.000 -100.000E-01 7.000 .000 .000 .0000 10.000 -100.0000 .0000 .0000 1 1 1 1 1 1 111111 001110 001110 111111 001110 001110 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 .0000 .0000 D D D D D D 1 1 1 1 2 2 .0000 760UB147 .4700E-05 X 1.0000 760UB147 .000 .6900E-03 5.0000 1 6 21 26 6 11 6 11 26 31 26 31 1 LIBR Asw.000 .850E+00 0.000 .0000 20.0000 .0000 X 1.0000 .Archive File * 2-STOREY FRAME * * * VERS 4 TYPE 5 VERT 2 UNIT 1 m kN NODE NODE NODE NODE NODE NODE MEMB MEMB MEMB MEMB MEMB MEMB PROP PROP 1 6 11 21 26 31 1 2 3 4 5 6 t C .6900E-03 5.000 Microstran V9 20:Examples • 359 .lib 1.lib 1.000 .6100E-06 1.000 31 .000 .
360 • 20:Examples Microstran V9 .
Microstran V9 20:Examples • 361 .
The output report shows the node masses and the frequency and mode shape for the first mode.Example 6 – Dynamic Analysis Example 6 demonstrates a dynamic analysis of a four-storey reinforced concrete building frame. The accompanying graphical output shows a rendered view of the structure and the third mode shape superimposed on a diagram of the structure. EXAMPLE 6 – DYNAMIC ANALYSIS 362 • 20:Examples Microstran V9 .
0000 0.0000 6.0000 8.0000 0.0000 8.0000 10.0000 0.0000 8.0000 10.0000 0.0000 10.0000 0.0000 0.0000 0.0000 8.0000 9.0000 0.0000 4.0000 4.0000 0.0000 10.0000 4.0000 12.0000 4.0000 0.0000 8.0000 4.0000 3.0000 0.0000 0.0000 9.0000 8.0000 111111 111111 111111 111111 111111 111111 111111 111111 111111 111111 111111 111111 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 0.0000 4.0000 0.0000 4.0000 12.0000 4.0000 9.0000 0.0000 6.0000 0.0000 12.0000 10.0000 0.0000 0.0000 10.0000 10.0000 8.0000 8.0000 12.0000 10.0000 12.0000 4.0000 9.0000 8.0000 3.0000 4.0000 6.0000 6.0000 12.0000 8.0000 10.0000 0.0000 0.0000 9.0000 3.0000 10.0000 4.0000 8.0000 4.0000 0.0000 0.0000 3.0000 12.0000 12.0000 6.0000 3.0000 0.0000 4.0000 12.0000 3.0000 4.0000 0.0000 3.0000 8.0000 12.0000 0.0000 0.0000 3.0000 8.0000 3.0000 8.0000 6.0000 0.0000 6.0000 0.0000 8.0000 4.0000 0.0000 10.0000 10.0000 10.0000 4.0000 12.0000 4.0000 0.0000 8.0000 4.0000 0.0000 0.0000 8.0000 4.0000 4.0000 0.0000 10.0000 12.0000 10.0000 0.0000 8.0000 8.0000 8.0000 0.0000 3.0000 12.0000 8.0000 10.0000 0.0000 12.0000 9.0000 4.0000 4.0000 10.0000 10.0000 0.0000 8.Archive File * DYNAMIC ANALYSIS EXAMPLE * 3D FRAME .0000 8.0000 6.0000 12.0000 10.3 bays x 2 bays x 4 storeys * * VERS TYPE VERT UNIT NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NODE NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS 4 5 3 1 m 1 2 3 4 11 12 13 14 21 22 23 24 31 32 33 34 41 42 43 44 51 52 53 54 61 62 63 64 71 72 73 74 81 82 83 84 91 92 93 94 101 102 103 104 111 112 113 114 121 122 123 124 131 132 133 134 141 142 143 144 31 32 33 34 41 42 43 44 51 52 53 54 61 62 63 64 71 72 73 74 81 82 83 84 91 92 kN T C 0.0000 9.0000 8.0000 8.0000 8.0000 12.0000 12.0000 4.0000 12.0000 6.0000 8.0000 10.0000 12.0000 10.0000 4.0000 0.0000 9.0000 0.0000 10.0000 12.0000 0.0000 10.0000 6.0000 0.0000 4.0000 10.0000 6.0000 3.0000 4.0000 9.0000 8.0000 4.0000 12.0000 9.0000 4.0000 4.0000 8.0000 12.0000 8.0000 9.0000 6.0000 0.0000 8.0000 3.0000 12.0000 12.0000 4.0000 12.0000 12.0000 10.0000 9.0000 4.0000 4.0000 8.0000 4.0000 10.0000 4.0000 8.0000 Microstran V9 20:Examples • 363 .0000 8.0000 0.0000 4.0000 0.0000 0.0000 12.0000 0.0000 8.
0000 10.0000 10.0000 10.0000 10.0000 10.0000 10.NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS NMAS MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB 93 94 101 102 103 104 111 112 113 114 121 122 123 124 131 132 133 134 141 142 143 144 1 2 3 11 12 13 21 22 23 31 32 41 42 51 52 61 62 71 72 73 81 82 83 91 92 93 101 102 111 112 121 122 131 132 141 142 143 151 152 153 161 162 163 171 172 181 182 191 192 201 202 211 212 213 221 222 223 231 232 233 241 242 251 252 261 262 271 272 281 282 283 284 291 292 293 294 301 31 32 33 41 42 43 51 52 53 31 41 32 42 33 43 34 44 61 62 63 71 72 73 81 82 83 61 71 62 72 63 73 64 74 91 92 93 101 102 103 111 112 113 91 101 92 102 93 103 94 104 121 122 123 131 132 133 141 142 143 121 131 122 132 123 133 124 134 1 31 61 91 2 32 62 92 3 10.0000 10.0000 10.0000 10.0000 10.0000 10.0000 10.0000 10.0000 10.0000 10.0000 32 33 34 42 43 44 52 53 54 41 51 42 52 43 53 44 54 62 63 64 72 73 74 82 83 84 71 81 72 82 73 83 74 84 92 93 94 102 103 104 112 113 114 101 111 102 112 103 113 104 114 122 123 124 132 133 134 142 143 144 131 141 132 142 133 143 134 144 31 61 91 121 32 62 92 122 33 Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z Z -X -X -X -X -X -X -X -X -X 10 10 10 10 10 10 10 10 10 20 20 20 20 20 20 20 20 10 10 10 10 10 10 10 10 10 20 20 20 20 20 20 20 20 10 10 10 10 10 10 10 10 10 20 20 20 20 20 20 20 20 10 10 10 10 10 10 10 10 10 20 20 20 20 20 20 20 20 30 30 30 30 31 31 31 31 31 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 364 • 20:Examples Microstran V9 .0000 10.0000 10.0000 10.0000 10.0000 10.0000 10.
610E+07 2.300 1.400 30 SHAP 0.230E+07 2.450E+00 1.300 1.00 RECT 300X300 0.300 1.000E-01 2.300 31 SHAP 0.00 RECT 300X300 0.MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB MEMB PROP PROP PROP PROP 302 303 304 311 312 313 314 321 322 323 324 331 332 333 334 341 342 343 344 351 352 353 354 361 362 363 364 371 372 373 374 381 382 383 384 391 392 393 394 33 63 93 4 34 64 94 11 41 71 101 12 42 72 102 13 43 73 103 14 44 74 104 21 51 81 111 22 52 82 112 23 53 83 113 24 54 84 114 63 93 123 34 64 94 124 41 71 101 131 42 72 102 132 43 73 103 133 44 74 104 134 51 81 111 141 52 82 112 142 53 83 113 143 54 84 114 144 -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X -X 31 31 31 30 30 30 30 30 30 30 30 31 31 31 31 31 31 31 31 30 30 30 30 30 30 30 30 31 31 31 31 31 31 31 31 30 30 30 30 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 X_beams Y_beams 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 000000 10 SHAP 0.170E-05 Microstran V9 20:Examples • 365 .300 1.000E-01 2.450E+00 1.00 RECT 400X300 0.170E-05 2 3.400 20 SHAP 0.00 End_X_columns Interior_columns MATL MATL END 1 3.300 RECT 400X300 0.
366 • 20:Examples Microstran V9 .
Microstran V9 20:Examples • 367 .
368 • 20:Examples Microstran V9 .
180. 122. 122. 119 Coplanar node 77 Copy 153 CQC 262 Crossing window 24 Cross-section 86 Ctrl+A 22. 122 Analysis Accuracy 271 Buckling 255 Dynamic 362 ECL 255 Elastic critical load 255. 15. 24. 186 Coordinate transformation 187 Coordinates 82. 23. 335 CAD Interface 241 CASE 101. 341 Archive File Input 167 Area 208 Area load 211 Area loading 112 AS 3600 317 AS 4100 279 AS 4600 279 AUSTROADS 200 AutoCAD 243 Axes Global 63 Load 105 Local 63 Member 63 Axial force 273 Axis Reference 83 Axis system 186 Cable 98. 358 COMB 175 Combination load case 114 Command Assistant 118 Comment 89 Compression-only 97 Concentrated 103 Condition number 74. 173 Catenary cable 98 CBEM 177 CCOL 178. 153 Ctrl+X 22. 358 Non-linear 97. 179 Check steel connections 301 Coefficient of thermal expansion 93 Collinear reference node 83 Color depth 15 Colors 20 Column buckling 255. 83 Applied loads 272 Archive file 167. 153 Ctrl+V 22. 124 Ctrl+C 22. 247. 288. 122. 26. 123. 28 Continuous beam 138 Coordinate systems 63. 123. 99.Index Bracing connections 296 Break line 120 Brittle fuse member 100 Broken line 65 BS 5400 200 BS 5950 279 BS 8110 317 Buckling analysis 255 Buckling modes 358 C A Acceleration 102 Accelerator keys 22. 354 Second-order 247 Angle section 64. 123. 241. 286. 274 CABLE 160 Cable member 98 CAD DXF 10. 122. 153 Index • 369 B Base plates 297 BBL file 202 Beam on elastic foundation 139 Bending moment 273 BFUSE 160 Boundary 129 Microstran V9 . 271 Configuration 20 CONLY 160 Connection data 300 Connection design 300 Connection output 304 Connection report 302 Connectivity 83 Context menu 3. 274.
88 Direction code 86 Directories 17 Discontinuity 107 Displacement 111 Display steel connections 302 DIST 107 Distortion 107 DOF 61. 119. 124 Ctrl+Z 22. 122. 124 Factor Moment of inertia 90 File type 19 Fixed support 87. 81 Delete 22. 286 Elastic foundation 146 EMF 8. 358 Elastic critical load 274 Elastic critical load analysis 255. 335 Dynamic analysis 93 Errors Macro Language Input 197 Example Archive file 180 BBL file 206 Continuous beam 342 Dynamic analysis 260. 23. 152. 122. 241. 243 END 175. 23. 153 Cursor 24 Curve 126 Customize 58 Cut 153 Cylindrical coordinates 82. 123. 81 Double-click 19. 124. 157 Fixed-end actions 250 Flexural shortening 250 Flexural-torsional buckling 255 Floor loading 112 Focus 153 Folders 17 Fonts 19 Form Load 103 Frame 76 Frame buckling 254 Fuse member 99 E Eccentricity 298 ECL analysis 255. 26. 286 Edit Member loads 12 Member properties 27 Node loads 12 Node properties 27 Effective length 274. 178. 154 Design data 176 Design group 66. 362 ECL analysis 358 HBL file 215 Member load 106 MLI 181 MLI file 198 Non-linear analysis 354 Portal frame 345 RC design 330 RC detailing 339 Space truss 349 Example jobs 37 Examples 341 Examples folder 18 Excel 276 Explorer 19. 122. 159.Ctrl+Y 22. 179 End line 120 Entities 155 Entity labels 80 Envelope 201. 273 Equivalent frame 69 370 • Index G Gap member 99 Generate 154. 122. 151 Export Analysis results 276 Archive file 167 DXF 243 Extra Buttons toolbar 57 F F5 22. 156. 153 Drawing 118 Drawing plane 124 Drivers folder 18 Duplicate members 124 Duplicate nodes 124 DXF 10. 163 Geodesic dome 149 Global axes 63 Graphics Input 117 Microstran V9 . 186 D Data folder 18 Data generation 182 Data tip 39 Degree of freedom 61. 15.
210 Member 103 Offset 205. 106. 143 HB loading 200 HBL file 207 Heavy Load Platform 200 Help About dialog box 36 Help toolbar 53 Home 22. 214 L Lane 207 Large residual 74 Lateral torsional buckling 255. 288 Launch 19 LIBR 160 Library 89 Limit 128 Linedraw.ttf 19 Load Axes 105 Concentrated 203 Distributed 202 Form 103 Knife 211 Lane 210 Line 203. 213 Type 104. 274 Import Archive file 167 DXF 242 MLI file 182 Incidence 83 Influence lines 107 Initial tension 98 Input load case 39 Input methods 79 Archive File Input 167 CAD Interface 241 Graphics Input 117 Macro Language Input 181 Standard Structures Input 135 Table Input 151 Insert after 153 Insert before 153 Instability 72.GRAV 173 Gravitational 102 Grillage 146. 162 Load Input toolbar 131 Local axes 63 H Hardware lock 18 Haunch 68. 163 Load case Combination 114. 74. 124 Hot-links 36 HSS truss connections 298 I Ill-conditioning 72. 23. 96. 271 MATL 173 MBLD 103. 162 Title 101. 83. 253 Installation 17 Insufficient support 72 Interface to user programs 276 Interruptible commands 25 Intersect 120 M Macro Language Input 181 Main window 39 Mass 93 Mass density 93 Master-slave constraints 96 Material Library 92 Name 92 Properties 92. 209 Scale 105 Truck 204. 285. 162 Primary 102. 122. 84 Cable 98 Connectivity 83 Definition 271 Distortion 107 Index • 371 J Job title 80 K K/N gap connection 298 K/N overlap connection 298 Microstran V9 . 214 Parameters 105 Point 203. 174 Mechanism 73 Mechanism instability 78 MEMB 170 Member 157 Axes 63.
76. 85. 158. 99. 341 Paste 153 P-delta effect 248. 59 P Page Setup 6. 174 NMAS 173 Node Coordinates 271 Coplanar 77. 28 Portal frame 142. 345 Prescribed displacement 111 Principal axes 64 Printing in Microstran 30 PRIS 160 Program folder 18 Prompt 39 PROP 171 N Natural modes 362 NDIS 111. 163 Load generation 163 Mass 93 Numbering 66 Properties 27 Restraint 67. 77. 276 Generation 156 Load 102.Forces 273. 247. 345 Results 273 Temperature 110 Type 97. 160 Menu bar 39 Menus 39 MGAP 160 Microstran V5. 182 MLI example 198 MLI file 198 Modelling 61 MOFF 170 Moment connections 295 Moment of inertia 92 Moment of inertia factor 90 MS LineDraw 19 MSPR 171 MsReset 20 MTMP 110. 174 MTYP 170 Müller-Breslau Principle 107 Multiple selection 28 Temperature 109 NODE 169 Noding eccentricity 298 Non-linear analysis 97. 354 Notes 4 Numbering members 66 Numbering nodes 66 Numbering sequence 80 O OK/Cancel toolbar 56 OpenGL 21. 32. 85 Pin-ended 76 Pixel format 21 Plane frame 147 Plastic fuse member 100 Pop-up menu 26. 189 Intersection 120 Load 103. 276 Fuse 99 Gap 99 Generation 159 Incidence 83. 164 Load generation 164 Non-Linear 250 Numbering 66 Orientation 84. 277 Rectangular axes 64 Rectangular coordinates 119 Reference axis 83 Reference node/axis 83 Registry 20 Microstran V9 . 249 PFUSE 160 Pin 67. 249 P-Delta effect 248. 237 Pin-ended 76 Properties 27 Release 67. 158. 345 Results 272 372 • Index Q Quantities 271 R Range 153 RC design 317 RC design report file 326 RC detailing 334 Reactions 274. 41 Orientation 84 Output window 39.5 36 MLI 181. 175 NDLD 102. 349 Displacements 272.
88. 120 Grid 120 Intersection 120 Mid/End 120 Nearest 122 Orthogonal 122 Perpendicular 121 Microstran V9 Sort 153 Space 22. 287 Stiffness 77 STRESS 10. 85 Release code 85 Reset 59 Residual 74. 91. 79 Standard Structures Input 135 Status bar 39 Steel connection design 293 Steel design 279 Steel design report file 292 Steel detailing 292 Steel member design 300 Steel restraints 56. 174 Temperature 109. 94 Rotate 187 S Scale Load 105 Screen resolution 15 Secondary axis system 186 Second-order analysis 247 Section Axis 90 Comment 89 Library 34. 122 Sign convention 64 Sign conventions 273 Slab 69. 110 Tension-only 97 Text editor 182 Text file 182. 89 Name 89 Properties 77. 79 Sub-frame 145 Subgrade modulus 140. 123. 110 Temperature gradient 109. 276. 124 Space frame 148 Space truss 77. 160. 349 Spherical coordinates 82. 137 SLAV 169 SMEM 176 Snap mode 39. 153 Shortcut keys 22. 79 Stretch 127 Strucad 292 Structure type 76.Relative coordinates 119 Release 76. 119. 186 Spiral 198 Splices 296 Spring 95 Spring support 88 SPRN 169 SSI 135 STAAD 10. 18. 58 Flat style 58 Large buttons 58 Reset 58 Tooltip 2. 5. 122. 309 Thermal expansion 109 Title 80 TONLY 160 Toolbars 39. 81 Structure unstable 73 STRUDL 10. 23. 274 Restraint 87 Restraint code 87 Results files 276 Right-click 26 Rigid frame 142 Rigid member offset 77. 271 Shape 90 Section axis alignment 90 Select cells 152 Select members 24 Select nodes 24 Selection box 24 Semi-rigid connections 95 Serial number 36 Settlement 111 SHAP 160 Shape 90 Shear 273 Shear area 91 Shear connections 295 Shear wall 68 Shortcut 19. 146 Subset 128 Support 36 T T44 200 Table Input 151 Technical support 36 TEMP 109. 31 Torque 273 Torsion constant 91 Translate 187 Trapezoidal 103 Index • 373 . 70.
227. 303 VRML 15. 77 Tributary area 113 Troubleshooting 254 Truck loading 199 Truss 62. 302. 287. 76 Parallel chord 141 Triangular roof 140 Truss connections 298 Trussed rafter portal frame 144 Tutorial 225. 41 W Web update 37 Window 128 Winkler foundation 140 X X connection 298 X-bracing 97 Xsteel 15. 349 U UDL 103 Unconnected member 75 Undo 153 Undo/Redo 118 Uniform 103 UNIT 168 Units 80 Unstrained length 98 User programs 276 V VERT 169 Virtual reality 15. 302. 294. 76 Zero stiffness 72. 232 Tutorial examples 37 Tutorials folder 18 Type Load 104 TYPE 168 Z Zero pivot 73.Tree view 151 Trestle 149 Triangular 103 Triangulation 76. 294. 287. 303 VR 15. 292 Y Y/T connection 298 Young's modulus 93 374 • Index Microstran V9 .
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