Characterizing Dynamic Responses of Rock Slopes to Near-Fault Pulse-Like Ground Motions

This research examines the dynamic response and failure mechanisms of slopes in near-fault regions subjected to pulse-like ground motions (PLGM). Utilizing shaking table tests and numerical simulations, a categorization method is developed using the analytic hierarchy process (AHP) to assess the effects of PLGM quantitatively. An energy-based approach, incorporating the ratio of seismic energy release (RSER), quantifies dynamic response variations more accurately. Results indicate that the acceleration amplification factor (AAF) values for PLGM (QP, MY, and LD seismic motions) are 114.22%, 62.22%, and 31.11% higher than those for NPLGM (WL seismic motion) at the slope shoulder (A8), and 131.1%, 73.33%, and 44.44% higher at the trailing edge of slope top (A9). Additionally, the Arias intensity amplification factor (AlAF) values for PLGM are 397.26%, 195.33%, and 64.32% stronger than those for NPLGM at A8, demonstrating that PLGM amplifies the dynamic response compared to NPLGM at increased elevations. Disaggregated average amplification factors (DAAF) analysis shows that PLGM triggers diverse responses based on their characteristics, with pronounced nonlinear amplification effects as elevation increases. Peak Fourier spectrum amplitude (PFSA) analysis shows that high rock masses are particularly sensitive to the high-frequency components of PLGM, while wavelet package transform analysis confirms that energy release is concentrated in the velocity pulse segment, significantly influencing the frequency domain response at various elevations. Seismic motions with different pulse characteristics induce varied behaviors, with higher frequency components causing stronger responses. These insights enhance understanding of rock slope responses in near-fault earthquakes and support seismic slope design in such regions.