Dynamic Response and Failure Mechanism of Slopes Subject to Near-Fault Pulse-Like Ground Motions

Numerous post-earthquake slope investigations demonstrate that slopes proximal to fault zones frequently experience serious damage. To investigate the dynamic response characteristics and failure mechanisms of slopes subjected to near-fault pulse-like ground motions, several groups of ground motion records at the same station during the same seismic event were selected. Using an overburden slope as a case study, a series of shaking table tests were conducted. The influence of pulse-like ground motions on slopes was systematically investigated by comparing the dynamic response and deformation characteristics and failure patterns of slopes under near-fault pulse-like and non-pulse-like seismic excitations, and validated through numerical simulations. The experimental results demonstrate that pulse-like ground motions can significantly amplify the dynamic response of slopes, and the slope produces greater deformations when subjected to this seismic excitation. Residual displacements in the slope’s overburden layer induced by the 0.4 g peak amplitude pulse-like motion were measured to be 1.96 times greater than those caused by equivalent-amplitude non-pulse-like seismic excitation. Furthermore, employing the limit analysis methodology, this study systematically investigates and quantifies the effects of pulse-like ground motions on Newmark permanent displacements in slopes. These findings provide valuable insights for the seismic design of slopes in fault zones.