Detail of a retaining wall in unsaturated soil. a retaining wall is a structure that is constructed with the goal of retaining or supplying some degree of lateral confinement to the ground or other loose materials. these retained or confined materials apply thrust pressures against the wall and tend to overturn it and slide. retaining walls are used in cases, for example, where there are abrupt changes in the slope of the ground. details cuts with dimensions and technical specifications. autocad - dwg.