Upper-bound approach based on failure mechanisms in slope stability analysis of spatially variable [formula omitted]-[formula omitted] soils

Abstract

This paper presents the novel use of kinematical failure mechanisms to analyse the slope stability of spatially variable soil. To preserve the upper-bound limit theorem when the internal friction angle varies spatially, the dissipation regions must be assumed as broken lines instead of straight lines for deterministic scenarios. Application of the kinematical failure mechanism provides high numerical efficiency of the algorithm implementation. Two failure mechanisms were considered: a 1-block failure mechanism and a 3-block failure mechanism. It is shown that the latter can be successfully applied to a wide range of slope inclinations and soil parameters. A detailed comparison with random finite limit analysis (RFLA) is provided. Numerical implementation of the proposed algorithm was used for analysing a variety of slope geometries and drained/undrained soil conditions. The proposed method is found to be promising for applications in the area of slope reliability analysis.