07- Introduction to Subsurface Investigation Planning Intro
Geotech Master
[{'start': '7.200', 'end': '10.510', 'text': 'Hello everyone, and welcome back to GeoTech Master.'}, {'start': '11.540', 'end': '13.210', 'text': "I'm excited you're joining me."}, {'start': '13.750', 'end': '16.410', 'text': "If you're passionate about geotechnical engineering,"}, {'start': '16.850', 'end': '18.390', 'text': 'this is the\nplace for you.'}, {'start': '19.200', 'end': '23.526', 'text': "In this video we're going to tackle the fundamental reasons why"}, {'start': '23.610', 'end': '27.892', 'text': 'geotechnical subsurface investigations are absolutely essential.'}, {'start': '29.110', 'end': '32.423', 'text': "Whether you're a seasoned civil engineer, a budding"}, {'start': '32.507', 'end': '37.283', 'text': 'geotechnical student, or simply someone fascinated by what'}, {'start': '37.284', 'end': '40.899', 'text': 'lies beneath our feet, this video will give you the'}, {'start': '40.941', 'end': '45.384', 'text': 'essential foundations for subsurface investigation planning.'}, {'start': '83.010', 'end': '86.230', 'text': "In this episode we'll answer some very important"}, {'start': '86.380', 'end': '89.721', 'text': 'questions, including why do we need to bother'}, {'start': '89.763', 'end': '93.670', 'text': 'with subsurface investigations in the first place.'}, {'start': '94.890', 'end': '98.824', 'text': "What's the big picture when it\ncomes to planning these investigations?"}, {'start': '99.930', 'end': '104.204', 'text': 'How do we get started, and what are the key things to keep in mind?'}, {'start': '104.770', 'end': '109.230', 'text': 'What are in situ and laboratory tests, and why do we need both?'}, {'start': '115.440', 'end': '120.740', 'text': "Now, before we get started, if you haven't\nhad the chance to watch my earlier series,"}, {'start': '121.540', 'end': '127.894', 'text': 'Geotechnical Investigation Essentials, I\nstrongly recommend you check that out first.'}, {'start': '128.520', 'end': '133.740', 'text': "Don't worry, I've provided a link in the\ndescription below for your convenience."}, {'start': '135.040', 'end': '137.737', 'text': 'It will give you the background knowledge that'}, {'start': '137.779', 'end': '140.754', 'text': 'makes this new content even more understandable.'}, {'start': '142.030', 'end': '146.860', 'text': 'We are moving onward now, and this new video is a part of'}, {'start': '146.960', 'end': '150.734', 'text': 'planning a geotechnical subsurface investigation program.'}, {'start': '155.520', 'end': '158.214', 'text': "Right then, let's get started."}, {'start': '158.700', 'end': '162.099', 'text': "We're going to begin with a basic idea of this video, and"}, {'start': '162.141', 'end': '166.363', 'text': "that's why we do geotechnical subsurface investigations."}, {'start': '166.780', 'end': '169.491', 'text': "Imagine for a moment you're planning to build a house,"}, {'start': '169.880', 'end': '172.714', 'text': 'or a skyscraper, or even a bridge.'}, {'start': '173.560', 'end': '178.112', 'text': 'Now, what would happen if you just started building'}, {'start': '178.196', 'end': '181.191', 'text': "without knowing anything about what's beneath the surface?"}, {'start': '181.940', 'end': '186.280', 'text': "It'd be like trying to bake a cake\nwithout knowing any of the ingredients."}, {'start': '187.795', 'end': '189.500', 'text': "It's a recipe for disaster."}, {'start': '201.698', 'end': '206.196', 'text': "These investigations are all about\nfiguring out what we can't see with the"}, {'start': '206.280', 'end': '211.980', 'text': "naked eye, but that has a huge impact\non a structure's stability and safety."}, {'start': '218.075', 'end': '221.550', 'text': 'In our previous videos, we mentioned that our starting'}, {'start': '221.700', 'end': '225.120', 'text': 'point will be the available guidelines, but these'}, {'start': '225.162', 'end': '228.764', 'text': 'should be considered just that, a starting point.'}, {'start': '229.580', 'end': '232.738', 'text': 'We always need to be ready to make changes as the'}, {'start': '232.780', 'end': '236.370', 'text': 'investigation moves along, depending on what we find.'}, {'start': '237.270', 'end': '242.981', 'text': 'If the results show that the subsurface\nconditions are uncertain or highly variable,'}, {'start': '243.065', 'end': '245.324', 'text': 'we will need to collect more samples.'}, {'start': '246.220', 'end': '248.010', 'text': "It's all about\nbeing adaptable"}, {'start': '248.110', 'end': '250.250', 'text': 'and prepared for\nthe unexpected.'}, {'start': '256.750', 'end': '261.863', 'text': 'So, how do we get from nothing to a solid\nunderstanding of the subsurface conditions?'}, {'start': '262.510', 'end': '264.764', 'text': 'Well, it all begins with a good plan.'}, {'start': '265.630', 'end': '271.570', 'text': 'The planning process involves a whole\nrange of steps, such as defining our objectives.'}, {'start': '272.210', 'end': '274.364', 'text': 'What are we hoping to find out?'}, {'start': '274.800', 'end': '277.590', 'text': 'Choosing the right methods for testing and sampling.'}, {'start': '278.910', 'end': '282.090', 'text': 'Interpreting the results and applying them to our designs.'}, {'start': '287.983', 'end': '291.237', 'text': "Once we've determined what kind of samples and"}, {'start': '291.279', 'end': '295.159', 'text': 'how often we need them, the next step is to decide which'}, {'start': '295.160', 'end': '298.333', 'text': 'combination of in-situ and laboratory tests will'}, {'start': '298.375', 'end': '302.114', 'text': 'provide reliable measurements of our design parameters.'}, {'start': '303.360', 'end': '307.046', 'text': 'Now, these are really the heart of what we do and'}, {'start': '307.088', 'end': '310.814', 'text': 'there are advantages and disadvantages to each.'}, {'start': '316.610', 'end': '320.377', 'text': 'Laboratory tests allow us to make direct measurements of'}, {'start': '320.419', 'end': '324.770', 'text': 'important design parameters like strength and compressibility.'}, {'start': '325.890', 'end': '331.864', 'text': 'We can precisely control the boundary\nconditions like confining pressure and drainage.'}, {'start': '332.770', 'end': '337.370', 'text': "These tests are great for seeing\nwhat's going on with the material itself."}, {'start': '343.280', 'end': '347.040', 'text': 'However, laboratory tests have their own issues such as,'}, {'start': '347.600', 'end': '350.953', 'text': 'the tests are done on small specimens, which might not'}, {'start': '350.995', 'end': '355.080', 'text': 'fully represent the properties of the entire area in the field.'}, {'start': '356.480', 'end': '359.979', 'text': 'Sample disturbance during testing can have an impact on'}, {'start': '360.021', 'end': '364.074', 'text': 'the results and this is something we always have to consider.'}, {'start': '369.890', 'end': '374.403', 'text': 'in-situ tests are done directly in\nthe ground with minimal disturbance.'}, {'start': '374.970', 'end': '379.496', 'text': 'They measure soil and rock properties\nunder real in-situ stress conditions.'}, {'start': '380.330', 'end': '386.386', 'text': 'Some in-situ tests like the CPT can\nprovide a continuous profile as we go deeper,'}, {'start': '386.470', 'end': '391.244', 'text': 'meaning we get a good idea of what\nthe ground is doing at different levels.'}, {'start': '396.920', 'end': '400.000', 'text': 'in-situ testing has some disadvantages too.'}, {'start': '400.360', 'end': '406.314', 'text': "Most of the time in-situ tests don't give us\ndirect measurements of design parameters."}, {'start': '407.800', 'end': '411.876', 'text': 'We often have to use empirical correlations or solutions of'}, {'start': '411.918', 'end': '416.174', 'text': 'boundary value problems to work out the parameters we need.'}, {'start': '416.620', 'end': '420.059', 'text': 'This can create a bit of additional uncertainty due'}, {'start': '420.143', 'end': '423.430', 'text': 'to the way we are estimating the design parameters.'}, {'start': '428.840', 'end': '430.040', 'text': "Here's a key point."}, {'start': '430.480', 'end': '434.080', 'text': 'In-situ and laboratory tests work together really well.'}, {'start': '434.900', 'end': '437.966', 'text': 'In-situ tests are often a big part of exploration'}, {'start': '438.008', 'end': '441.240', 'text': 'programs because they tend to be more economical.'}, {'start': '442.523', 'end': '445.695', 'text': 'Laboratory tests give us direct measurements'}, {'start': '445.737', 'end': '449.051', 'text': 'of design parameters, which we can use directly'}, {'start': '449.052', 'end': '451.764', 'text': 'in our designs and also we can use them to'}, {'start': '451.806', 'end': '455.490', 'text': 'check the accuracy of results from in-situ tests.'}, {'start': '456.200', 'end': '461.196', 'text': 'And on bigger projects, we can do enough laboratory tests to develop'}, {'start': '461.238', 'end': '467.236', 'text': 'site-specific correlations to reduce\nthe uncertainty with in-situ results.'}, {'start': '467.900', 'end': '472.450', 'text': 'We will be going through this in more detail\nas we move through this series of videos.'}, {'start': '473.320', 'end': '474.780', 'text': 'This was only an overview.'}, {'start': '480.560', 'end': '482.000', 'text': 'So there you have it.'}, {'start': '482.330', 'end': '485.700', 'text': "We've looked at why geotechnical investigations are critical,"}, {'start': '486.280', 'end': '492.874', 'text': 'what the planning process involves and the\nvalue of both in-situ and laboratory testing.'}, {'start': '493.570', 'end': '495.200', 'text': 'I hope you found\nthis useful.'}, {'start': '501.290', 'end': '503.950', 'text': 'Before you go, I have a question for you.'}, {'start': '504.430', 'end': '507.370', 'text': 'What type of geotechnical investigation challenges'}, {'start': '507.412', 'end': '510.870', 'text': 'have you faced in your work and how did you handle them?'}, {'start': '512.110', 'end': '514.472', 'text': 'Share your answers in the comments section below.'}, {'start': '515.270', 'end': '517.010', 'text': 'I really want to\nhear from you.'}, {'start': '517.310', 'end': '520.204', 'text': 'Also, please share this video with your friends'}, {'start': '520.246', 'end': '523.430', 'text': 'who might find this topic interesting and useful.'}, {'start': '535.723', 'end': '541.423', 'text': "If you found this video helpful, please\ngive it a like and if you haven't already,"}, {'start': '541.690', 'end': '545.030', 'text': 'subscribe to the channel for more geotechnical goodness.'}, {'start': '546.210', 'end': '549.182', 'text': "By doing so, you'll introduce this video to more"}, {'start': '549.224', 'end': '552.864', 'text': 'people and help us to continue on this journey together.'}, {'start': '553.970', 'end': '559.486', 'text': 'And for those of you who would like to\nsupport me further, you can purchase this course,'}, {'start': '559.570', 'end': '565.521', 'text': "where you'll find not only the slides from\nthis presentation, but also a handy mind map to"}, {'start': '565.522', 'end': '568.309', 'text': 'help you learn this material quickly, as well'}, {'start': '568.351', 'end': '571.836', 'text': 'as a package with all of the related resources.'}, {'start': '572.610', 'end': '577.450', 'text': 'All the links to the courses and earlier\nvideos are in the description below.'}, {'start': '583.430', 'end': '588.824', 'text': 'These are also some references\nthat I have used to prepare this course.'}, {'start': '594.020', 'end': '598.056', 'text': "Thanks for watching and I'll see you in the next video."}]