Stability of Soil Block on Low Interface Friction Plane With and Without Side Supports

Abstract

Slope instability is a challenging problem in geotechnical engineering. The main focus of this paper is to investigate the stability of a soil block, with and without side supports, resting on a low interface friction plane by employing a three-dimensional finite element analysis (3D FEA). In the numerical model, the soil block is modeled as a volume element with Mohr-Coulomb material in a drained condition. Interface elements are used at the bottom plane in order to capture the shear sliding on the interface plane. Side interface elements with fully rough surfaces are also used in the slip analysis with side supports. A failure analysis is performed by means of the gravity loading method. The results of 3D FEA are compared with those of the existing physical models for both cases. Extensive parametric studies of a slip analysis with side supports are carried out in order to develop an empirical equation for the stability number as a function of four normalized parameters. Finally, the paper presents an application of the proposed equation to the prediction of the failure width and the required width for the excavation of an actual mine.