An Empirical Approach to Characterization of Key Failure Modes in Spatially Variable Slope Stability Analysis

摘要

As one main source of uncertainties in geotechnical discipline, the spatial variability of soil properties should be fully addressed in the assessment of slope system failure probability.A fundamental issue associated with the slope system accounting for spatial variability is the identification of representative slip surfaces (i.e.,key failure modes) based on which the response of slope system can be surrogated.This paper aims to present an empirical procedure which can distinguish the key failure modes by considering the correlation coefficients in factor of safety among a large number of potential slip surfaces.The correlation coefficient in factor of safety between any two slip surfaces is efficiently calculated based on the assumption that the closer two slip surface are located, the higher probability in two identical factors of safety.The deterministic slip surface that has the lowest factor of safety is selected to be the first key failure mode and the correlation coefficients between other slip surfaces and deterministic slip surface are adopted to characterize the rest key failure modes.The proposed methodology is illustrated via a cohesive spatially variable slope and validated against the existing results in the literature.The comparative investigation shows that the obtained key failure modes can dominate the response of slope system and the proposed empirical approach acts as an efficient tool for identifying the key failure modes in slope system reliability.