Elasto-plastic analysis of jointed rock masses using the numerical manifold method

An elasto-plastic model of intact rock is established and added to the numerical manifold method (NMM) for deformation and strength analysis which is an improvement to the NMM, for the existing NMM can only offer an elastic solution. The model is based on the assumption that the extended von Mises' yield criterion, isotropic hardening (softening) rule, and the associated flow rule are applicable to the material. The corresponding VC++ program is then developed, and numerical simulations of jointed rock masses are carried out using the program. The results proved to be correct and some new findings were obtained, which indicate that the discontinuities in the rock mass have a distinct influence on the strength and deformability characteristics of the rock mass.