Evaluating the dynamic response and failure process of a rock slope under pulse-like ground motions

Abstract

AbstractEarthquake-induced landslides represent a significant proportion of seismic hazards in mountainous areas. Numerous slope stability analysis methods exist; however, only a few consider the interactions between pulselike seismic waves and landslides. This study investigates the seismic response characteristics of a homogenous step-like slope to evaluate the acceleration ground motion amplification along the surface. Parametric analysis focusing on the effect of pulselike waves on the slope is conducted using the finite difference modeling code Flac 3 D. Based on the numerical simulation results, pulselike seismic waves greatly influence the acceleration and velocity amplification factor (MPGA & MPGV), with maximum amplification usually obtained at the slope’s crest, where sliding failure initiates. The MPGV of rock slope under pulselike seismic waves is 9.3% higher than near-fault non-pulselike and 16% higher than the far-fault. The displacement for pulselike seismic waves is 20% higher than non-pulselike waves. The dynamic failure analysis presented deep failure for the slope under pulselike seismic wave compared to the non-pulselike. The dynamic failure calculated using Flac 3 D agrees with the results of Newmark-type displacement, with a marginal error between 1 and 8%. The study’s findings can be factored into reinforcing seismic engineering design and probabilistic stability analysis.

Keywords

• Velocity pulses
• slope dynamic response
• magnification effect
• failure process