Impact of Earthquakes on Cantilever Retaining Walls

Cantilever retaining walls are required to retain earth at a change in ground elevation. As the nonseismic design of cantilever retaining walls is well discussed elsewhere, this paper deals mainly with seismic considerations. In the present state of knowledge, the recommended method of obtaining seismic earth forces is that using equivalent static coefficients, which was proposed by Mononobe and Okabe, and is based on Coulomb's theory. This method has been implemented in an optimization computer program for the dimensioning of retaining walls. Graphs were prepared, which illustrate the influence of earthquakes on the minimum required wall dimensions and reinforcement, covering a broad spectrum of values of the parameters describing the backfill material and the seismic coefficient. Besides examining that influence, these graphs can also be used as an aid for the design of retaining walls, since they provide information about a wide range of cases that appear in practice.