: The purpose of this paper is to describe the anistropic inelastic behavior of sedimentary rocks. We propose to develop an elastoplastic model, based on representative invariant tensor functions theory. In this model a non associative flow rule is used. Plastic potential and yield function are generalized from Drucker-Prager criterion. The anisotropy of material is described by using a fourth order structural tensor. The parameters and validation of the model are proceed on laboratory data obtained on a shale from Tournemire (France).
Many underground works, such as chemical and nuclear waste storage and oil boreholes are located in anisotropic rocks. The design and stability analysis of such structures requires knowledge of the deformation and failure of these rock materials.