Effects of subsoil and backfill conditions on seismic displacement of gravity type retaining walls

Based on results from a series of model shaking tests conducted under normal gravity, a simplified procedure to evaluate earthquake-induced displacement of gravity type retaining walls was proposed. In the procedure, sliding and overturning displacements of the model wall due to accumulation of residual shear deformations of subsoil are computed. Based on these displacements, formation of failure plane in the backfill soil is evaluated. After its formation, sliding and overturning displacements of the model wall are computed by using the Newmark's sliding block method. The effect of strain softening in the backfill that is associated with the formation of failure plane is considered in evaluating the threshold acceleration and the threshold overturning moment to be employed in the Newmark's method. It could reasonably simulate the model test results conducted under different subsoil and excitation conditions.