Earthworks are engineering works created through the processing of parts of the earth's surface involving quantities of soil or unformed rock. Shoring structures An incomplete list of possible temporary or permanent geotechnical shoring structures that may be designed and utilised as part of earthworks: Mechanically stabilized earth Earth anchor Cliff stabilization Grout curtain Retaining wall Slurry wall Soil nailing Tieback (geotechnical) Trench shoring Caisson Dam Gabion Ground freezing Gallery Excavation Excavation may be classified by type of material: Topsoil excavation Earth excavation Rock excavation Muck excavation – this usually contains excess water and unsuitable soil Unclassified excavation – this is any combination of material types Excavation may be classified by the purpose: Stripping Roadway excavation Drainage or structure excavation Bridge excavation Channel excavation Footing excavation Borrow excavation Dredge excavation Underground excavation Civil engineering use Typical earthworks include road construction, railway beds, causeways, dams, levees, canals, and berms. Other common earthworks are land grading to reconfigure the topography of a site, or to stabilize slopes. Military use In military engineering, earthworks are, more specifically, types of fortifications constructed from soil. Although soil is not very strong, it is cheap enough that huge quantities can be used, generating formidable structures. Examples of older earthwork fortifications include moats, sod walls, motte-and-bailey castles, and hill forts. Modern examples include trenches and berms. Equipment Heavy construction equipment is usually used due to the amounts of material to be moved — up to millions of cubic metres. Earthwork construction was revolutionized by the development of the (Fresno) scraper and other earth-moving machines such as the loader, the dump truck, the grader, the bulldozer, the backhoe, and the dragline excavator. Mass haul planning Engineers need to concern themselves with issues of geotechnical engineering (such as soil density and strength) and with quantity estimation to ensure that soil volumes in the cuts match those of the fills, while minimizing the distance of movement. In the past, these calculations were done by hand using a slide rule and with methods such as Simpson's rule. Earthworks cost is a function of hauled amount x hauled distance. The goal of mass haul planning is to determine these amounts and the goal of mass haul optimization is to minimize either or both. Now they can be performed with a computer and specialized software, including optimisation on haul cost and not haul distance (as haul cost is not proportional to haul distance). See