Purpose of retaining wall
Retaining walls are designed to restrain soil, or engineering fill, at an angle steeper than the material’s angle of repose – the steepest angle it can hold naturally, without failing. To do this, they need to be able to withstand the horizontal – or lateral – earth pressure, exerted by the material being retained.
Retaining walls make sloped areas functional. Essentially, the walls flatten the slope so that water and soil don’t flow downward. Retaining walls can also help provide pedestrian access to a sloped area. Instead of walking up and down the slope, a retaining wall makes it easier to walk since the area is flat.
