Slope Stability Computations with Nonlinear Failure Envelope using Generalized Procedure of Slices and Optimization Techniques

Abstract

The study pertains to the development of an autosearch technique for locating the critical shear surface and the corresponding minimum factor of safety without any prior assumption regarding its shape, for slopes in soils having nonlinear strength envelopes. Sequential unconstrained optimization in conjunction with Janbu’s generalized procedure of slices has been used in the analysis. Results have been obtained for both linear and nonlinear failure envelopes and compared. It has been observed that in case of nonlinear strength idealisation, the critical slip surface is sensitive to the magnitude of pore water pressure parameter (rµ,) and the factor of safety versus rµ. relationship is nonlinear. The developed method has been found to be effective for the problems studied.