Hydraulic Fracture Propagation in Rock Mass with XFEM

Modeling hydraulic fracture propagation in rock mass within the extended finite element method (XFEM) is presented in this paper. The XFEM framework is integrated by fully coupling the model with fluid flow and rock deformation in the proposed algorithm. The fluid within the fracture is considered as an incompressible Newtonian fluid. In the proposed formulation, the first-order generalized shape functions for the nodes around the cracks are used, and the augmented Lagrange method combined with the mortar method (segment to segment) is used to treat the contact of the two cracks faces. The crack width, the crack length, and the pressure in the crack in the presence of a natural fracture are studied.