Abstract
The knowledge for the failure process of rock slope is of fundamental importance to asses the slope stability.
In this paper, a numerical procedure to analyze the failure process of rock slope by the Displacement Discontinuity Method (DDM) is proposed, then the failure process and the failure mode of homogeneous rock slope are discussed.
In the numerical analysis, the rock slope is modeled as the elastic material and the process of crack initiation and crack propagation is analysed by DDM. The cohesion of the crack surfaces is treated to be dependent on the displacement discontinuity of the crack. It is made clear that the failure process and the failure mode of rock slope is closely connected with the strength characteristics of the crack surfaces as well as the slope angle by demonstrating the numerical results. It is shown that the slope failure occurs by connecting the conjugated shear cracks, in the case that the critical value of crack shear displacement (CSD) is relatively small. On the other hand, the tensile fracture occurs at the crack tip of the shear crack plays an important role in progressing the slope failure, in the case that the critical value of CSD is relatively large.
The critical value of stability factor obtained by the present analysis agrees with the experimental value reported by OKAMURA et al., but dose not with that obtained by the conventional limiting equilibrium analysis.
It is pointed out that the influence of the slope angle on the slope stability is less than that predicted by the conventional limiting equilibrium analysis, although the critical value of stability factor increases with decreasing the slope angle.
