Rapid Assessment of Seismic Slope Stability Considering the Increase of Excess Pore-Water Pressure

Abstract

For soil slopes, excess pore-water pressure (EPWP) buildup in soil elements is a major cause of slope failure during seismic loading. In this study, an EPWP coefficient was proposed and integrated into the simplified Bishop method to rapidly assess the influence of EPWP buildup on seismic slope stability and to calculate the slope factor of safety. To determine the value of the EPWP coefficient, numerical simulations of soil slopes with different inclinations were performed. During seismic loading, the decrease in the factor of safety for the slope can be clearly observed with the increase in EPWP. It was found that the value of the EPWP coefficient was negatively correlated with the slope angle. A linear function was employed to fit the correlation between the EPWP coefficient and the slope angle. It enables easy prediction of the EPWP coefficient based on the slope geometry and further facilitates seismic slope stability analysis that considers the EPWP buildup.