Study on dynamic response of slope under near-fault pulse-like ground motion

Abstract

Compared with far-field ground motion, the most significant feature of near-fault pulse-like ground motion is the long-period, large-scale velocity pulse. This paper proves through statistical analysis that near-fault pulse-like ground motion is an important cause of slope damage and landslide. And use numerical simulation software FLAC3D to establish a homogeneous rock slope model, select near-fault ground motions with velocity pulses and non-pulse near-fault ground motions, and use an improved energy method to identify and extract the selected near-fault ground motions. The dynamic response of the slope under the action of near-fault ground motions with and without velocity pulses is comparatively studied, and the dynamic response law of the slope under the original records, pulse records, and residual records of pulse-like ground motions is explored. The research results show that the near-fault ground motions with velocity pulses can cause a greater dynamic response than ground motions without velocity pulses. There is an elevation magnification effect in the PGA distribution of the slope horizontally. The shorter-duration pulse record can cause a larger dynamic response, and the PGA magnification factor under the effect of the residual record is smaller than the original record. The velocity pulse strengthens the earthquake damage to the slope, and the slope produces a stronger dynamic response.