Risk Assessment of Slope Failure Using Assumption of aximum Area of Sliding Massand Factor of Safety Equal to Unit

Abstract

"This paper aims to develop an effective tool for quantifying the risk of slope failure and identifying the sources of failure risk by combining the limit equilibrium method and the assumption of maximum area of sliding mass with factor of safety�1. The assumption adopted in this study is firstly validated through the results from the homogeneous slope model, the laboratory experiment, and the smoothed particle hydrodynamics (SPH) program, respectively. Secondly, the proposed method is implementedthroughthequantificationofslopefailureriskandtheidentificationoffailuresourcesforahomogeneousslopeand a cohesive slope. The conventional method which quantifies the failure risk based on the slip surface with minimum factor of safety(FS)isalsoperformedtoenablethecomparisonwiththeproposedmethod.Thecomparativestudyhasdemonstratedthat the conventional method tends to underestimate the failure risk due to the negligence of the whole failure process as compared withtheproposedmethod.ThefailureriskhasatendencytoincreaseasverticalspatialvariabilityoffrictionangleandSugrowless significant for both proposed method and conventional method. However, the failure sources identified by the conventional methodaremorelikelytodecreaseastheverticalspatialvariabilityofSu becomeslesssignificantforcohesiveslope,whereasthe proposedmethodisabletofindanearlyconstantnumberoffailuresourcesbyconsideringthewholeprocessofslopefailure.Asa result, it is worthwhile to point out that attention is highly recommended to be focused on the failure sources when the spatial variability is less significant, even if it is not considered during the risk mitigation and reinforcing works. "