Displacement-Based Probabilistic Seismic Demand Analyses of Earth Slopes in the Near-Fault Region

Abstract

Near-fault pulses can result in high seismic demands on slopes in the proximity of a fault. A probabilistic methodology to capture the effects of near-fault pulses on seismically-induced slope displacements is proposed. This methodology allows for a separate and more adequate treatment of the sliding displacement of slopes when these are subject to pulse-like near-fault forward directivity motions. Simplified pulse parameters are used to predict displacements for cases where the near-fault pulses may induce resonances in the slope. The method explicitly includes the effects of near-fault pulses both on the ground shaking and nonlinear seismic response of slopes. An example application illustrates the use of the proposed procedure. Results show that the proposed approach increases the predicted earthquake-induced displacements of earth slopes located near the fault. Finally, the proposed procedure generates hazard deaggregation plots that are a useful tool for selecting ground motions for the design of slopes near faults.