Numerical Simulation of Mechanical Movement of Layered Rock Slopes

Different styles of rock slope movement have been observed in sedimentary and crystalline rock. In rock slopes, the orientation of the main set of discontinuities relative to the orientation of the slope face may govern the mode of movement. In this paper, two numerical codes, finite and discrete element codes, were used to examine three modes of movement; buckling, toppling and bilinear rock slopes. To simulate the effect of long-term weathering processes that is regularly observed in exposed rock slopes, the intact tensile strength of the rock is changed, and the impact of this change is tracked. In toppling, if sliding is allowed along the main set of joint, tensile strength of the intact rock is a key factor in controlling such movement. The buckling analyses also showed that the tensile strength of the intact layers might be an important factor in controlling the stability of slopes prone to buckle. In the bilinear movement, the finite and discrete element showed good agreement in their observed behaviour and was able to develop passive and active blocks during the failure process due to tensile strength reduction.