Approaches to the design of cantilever retaining walls

Cantilever (stem and pad) retaining walls are among the simplest earth-retaining structures to construct, and accordingly may offer significant economic benefits. Their design involves use of bearing capacity and sliding stability theory, and application of the factors of safety laid down in the code to which the designer is working. Two typical L-shaped cantilever walls founded on and retaining dry cohesionless soil are considered, designed in accordance with the procedures given in CP2:1951 and BS 8002:1994. It is shown that the width of the foundation base depends upon which philosophy of factor of safety, and hence which code, is adopted. It is also shown that BS 8002:1994 produces larger (more conservative) foundation bases than the CP2:1951 it replaces, although the difference is significant only for more steeply sloping backfills and deeper foundations.