Practical reliability analysis for earthquake-induced 3D landslide using stochastic response surface method

Abstract

This study investigates the effect of spatial variability on the stability of a real 3D slope subjected to earthquakes by conventional Monte Carlo simulation (MCS) and a stochastic response surface method. The stochastic response surface method used in this study (VRSRSM) was combined with a variance reduction method due to spatial averaging of soil parameters in slope failure to reduce a large computational load due to the realization of spatially correlated input parameters in three-dimensional space. In order to verify the applicability of the stochastic response surface method with a variance reduction method for 3D slope reliability, the safety factor for a simple 3D slope under non-seismic and seismic conditions was analyzed by MCS and VRSRSM. The VRSRSM was applied to risk evaluation of deep-seated landslides caused by the 2016 Kumamoto earthquake along with backcalculation of strength parameters based on the slope failure geometry and field investigation.