Two- and three-dimensional analyses of translational slides in soils with nonlinear failure envelopes

Abstract

This paper aims to assess the effect of nonlinearity of the soil shear strength envelope on the sliding mass configurations and the minimum two- and three-dimensional factors of safety for slopes susceptible to translational failure in both static and seismic conditions. An extensive parametric study was conducted using slope models and nonlinear soil strength envelopes that simulate translational failure case histories. Analysis of the results led to the development of stability charts that do not require an iterative procedure when determining the factors of safety. The introduction of a two-dimensional stability number and three-dimensional stability function, the values of which depend on the degrees of nonlinearity of the involved soils’ strength envelopes, has made it possible to develop such charts. These charts give the practicing geotechnical engineer a reliable and fast method to analyze translational failures. Using available software in such an analysis can be complicated if shear resistance along the sliding mass vertical sides and nonlinearity of soil shear strength envelopes are considered. Numerical examples and a case history are given to verify the reliability and illustrate the different applications of these charts.