Stability estimation of slopes having their slip surface determined by means of the STAB-3D method based on sliding body equilibrium analysis

Abstract

Most of the three-dimensional analyses of landslides are based on simple 2D methods analysing chosen characteristic flat sections of the analysed sliding body. Assumptions of the method of flat limit equilibrium analysis for a spatial solution have been elaborated. This is a combination of 2D analysis of flat sectional views and 3D analysis of the landslide’s sliding body, which disregards any stress that does not affect equilibrium. It is assumed, however, to apply only when dealing with structural slope failure (i.e. when the soil layers have the predisposition to shape the determined slip surface with a consistent decrease and explicit slide direction). This can also apply when examining the stability of a scarp or slope for the layered soil of potential slip surfaces and slide direction to be defined. The basic assumptions, equilibrium equations, and practical usage of the method have been described for an exemplary landslide. This method allows one to define in a straightforward manner the stability of slopes, to plan a way of preventing potential landslides, and to control those that have already arisen.