The use of numerical methods for the design of projects in rock masses is increasingly predominant with the increase in digital computing capacities. When the density of fractures is high, it is advantageous to adopt a homogenization approach. However, several difficulties related to fracture geometry and mesh generation emerge. Several attempts were done to overcome this problem and to calculate the mechanical elastoplastic parameters (Pouya & Ghoreychi 2001; Min & Jing 2003; Chalhoub 2006, 2010; Pouya & Chalhoub 2008; Bidgoli et al. 2013; Souissi et al. 2020). However, the numerical generation of the postpeak curves, which are of main importance to estimate a rockmass deformability in the plastic phase, is rarely found in the literature.
In the present work, a methodology based on the combined use of the discrete fracture network and the Finite Element Method is proposed and applied to a fractured rock mass containing two families of nonpersistent fractures to estimate its equivalent elastoplastic behavior. The proposed methodology based on the work of Pouya & Ghoreychi 2001, and Chalhoub 2010 has proven its efficiency in the generation of the homogenized stress-strain curves using Disroc© JFEM software, particularly in the post-peak phase. The homogenized anisotropic elastoplastic parameters were deduced for several directions of loading. The numerical curves show that the degree of anisotropy of a rockmass may differ from the elastic to the plastic post-peak phase. They also confirm that a rockmass may have several post-peak behaviors in terms of brittleness and ductility according to the load direction.