Slopes in soils and rocks are found in nature and in-made structures. Highways, dams, levees, canals and stockpiles are constructed by sloping the lateral faces of the soil because slopes are generally less expensive than constructing the wall. Natural forces such as wind and water change the topography on Earth and other planets, often creating unstable slopes. There are a number of techniques such as anchor blocking, soil nailing, retaining wall and the use of geo grids in embankments.
