Numerical modeling of normal wedge indentation in rocks

This paper deals with the numerical modeling of the problem of wedge indentation into an elasto-plastic half-plane. It focuses on the initial regime of the indentation process (prior to the initiation of a tensile fracture), in which energy is solely dissipated in a diffuse mode. The main issues that need to be addressed in modeling such a problem are first discussed: preservation of self-similarity, accuracy, and computational efficiency. Then, a comparison between numerical and analytical results based on a cavity expansion model is presented. The numerical results are shown to support a major prediction of the cavity expansion model, namely that the indentation process is predominantly controlled by a single number γ, which is a function of the wedge angle, the unconfined compressive strength of the rock, and its elastic modulus.