Anisotropy is an important feature of sedimentary and metamorphic rocks. This character affects opening stability and must be considered in design. So many laboratory tests are done to consider the influence of anisotropy on mechanical behavior and failure strength of such rocks. Introduction: Numerical modeling is an effective tool in design of structures and stability analyses. Because of computational complexity and the difficulty of determining the necessary elastic constants, it is usual for only the simplest form of anisotropy, transverse isotropy, to be used in design analyses. The peak strengths developed by transversely isotropic rocks in triaxial compression vary with the orientation of the plane of isotropy, foliation plane or plane of weakness, with respect to the principal stress directions. Methodology and Approaches: In this study the behavior of a transversely isotropic rock under triaxial loading is considered by using distinct element method due to its potential to modeling failure process of anisotropic materials and because of its ability to monitoring failure of these rocks under uniaxial and triaxial conditions. The bonded-particle discrete element method with embedded smooth joints was applied to model the mechanical behavior of transversely isotropic rock with systematic verifications. Particle Flow Code 2D (PFC2D) developed by Itasca was applied in this study to employ the bonded-particle DEM. The bonded particle model was adopted to construct isotropic rock without weak planes, which was calibrated based on elastic modulus and strengths that have the least effect of weak planes. Then, the smooth joint model was inserted to … Journal Papers