Retaining walls are used to keep the soil in an upright position, at locations where sudden changes of the ground occur. The wall and the supporting foundation have to be designed for the lateral pressure exerted by soil, and checked for strength, overturning, and sliding.
Types of Retaining Walls
1. Gravity wall: Here, stability is provided by its own weight. It is usually of masonry or plain concrete construction. The plain concrete wall is preferred only if the height is less than about 3 m.
2. Cantilever retaining wall: This consists of a vertical stem and base slabs. The stem acts as a vertical cantilever, and the heel and toe slabs act as horizontal cantilevers.
3. Counterfort retaining wall: Here, the counterforts behave like vertical cantilever beams with a T-section and varying depth. The vertical slab (stem) is designed with a fixed boundary condition on three sides and is free at the top.
4. Buttress retaining wall: It is similar to a counterfort retaining wall, except that the transverse support walls are located on the side of the stem opposite the retaining material and act as compression struts.
5. Basement wall: The exterior walls at the basement of a building also act as retaining walls, with the top of the wall being restrained, due to the RC slab at the ground floor level.
