Before revision: This paper is focused on a rigorous variant of the shear strength reduction method (SSR) and the corresponding determination of safety factors. The SSR-based safety factor is defined as a solution of an optimization problem that is independent of the plastic flow rule and the space discretization. In case of nonassociative plasticity, a modified Davis approach is used .
After revision: This paper is focused on a rigorous variant of the shear strength reduction method (SSR) problem with applications to slope stability problems. This new variant is derived on the basis of recent results by Tschuchnigg et al. 2015, where limit analysis and a modified Davis approach is used .