upper bound solution for the stability of surcharged soil slope using nonlinear failure criterion

In this paper using the upper bound limit analysis method, the stability of soil slope, uniformly surcharged at the crest is investigated. according to the soil behavior at the failure state, a continuous failure criterion nonlinear function of confining stress, and soil initial density is considered. the stress field along the slip surface is entered into the limit analysis formulation according to the airy stress function. the ultimate uniformly distributed load is obtained by optimizing the virtual work equation. the effects of different parameters such as slope angle, soil unit weight, and initial density are investigated. considering the nonlinear effects of confining stresses leads to a reduction in the ultimate load. this reduction is more obvious in slopes with lower angles. according to the proposed formulation, with increasing soil density, the ultimate load of the slope stability is increased. the results for different slope angles are compared with those obtained from the limit equilibrium-based methods. the ultimate loads of the proposed method are in some cases lower and in some cases more than the results of different methods based on limit equilibrium.