Three-dimensional finite element analyses of embedded retaining walls supported by discontinuous earth berms

A series of three-dimensional finite element analyses has been carried out to investigate the effect of the removal of sections of an earth berm supporting an embedded retaining wall. For the particular wall-berm geometry and ground conditions considered in these analyses, relationships between the wall movement, the length of berm section removed, the spacing between successive unsupported sections, and the time elapsed following excavation are presented and discussed. The analyses show that, for a given elapsed time, wall movements are proportional to the length of the excavated berm section provided that the unsupported sections are sufficiently widely spaced. If the spacing between unsupported sections is reduced below some critical value, wall movements then depend on both the length of and distance between the excavated berm sections.