Stability of slopes

Abstract

Abstract Traditional analyses of earth slope stability are based on equilibrium considerations of “slices” into which the collapsing soil mass is divided. Such analyses require some static assumptions so that the system of equilibrium equations becomes determinate. It is proposed that the kinematics-based limit analysis be used to calculate the stability (factor of safety or the critical height), rather than using the limit equilibrium technique with arbitrary static assumptions (such as, for instance, inclination of forces between slices). The method described is straightforward, the analysis has a clear mechanical interpretation, and it stands on its own as a means of performing stability analyses for earth slopes. The method proposed, when used with identical failure mechanisms as in traditional slice methods, can be used to assess the static assumptions used in these conventional methods. It can be argued that all solutions using conventional slice methods can be bound by a rigorous upper bound solution and another approximate solution, both presented in this paper. Traditional solutions which fall beyond the range indicated lead to unrealistic consequences when interpreted in view of the collapse mechanism. A convenient technique for including the influence of the pore pressure on stability of slopes is shown, and results of critical height calculations for homogeneous slopes are presented.