Modeling of Rock Joints Under Cyclic Loading Conditions Using Discontinuous Deformation Analysis

The shear strength of rock joints is an important factor to be considered when analyzing the stability of jointed rock mass. Rock joints tend to have smaller shear resistances in the reverse shearing than that of the forward shearing. A conceptual model describing the general shear behavior of rock joints under cyclic loading and the Barton-Bandis joint model considering the surface roughness degradation are implemented into the two-dimensional discontinuous deformation analysis (DDA) model. The modified DDA model is empirically validated by cyclic shear tests on two types of rock joints. Numerical simulations agree well with the experimental results, indicating that the DDA model is capable of describing the varying shear behaviors of rock joints subjected to cyclic loading conditions.