Numerical modeling of fracture process using a new fracture constitutive model with applications to 2D and 3D engineering cases

The overwhelming majority of experimental and numerical tests show the dependence of mechanical response on discontinuities (such as joints, faults, and bedding plane). In this study, fracture process is numerically investigated using finite-difference method. A quasi-continuum model (assuming that the real rock mass represents the sum of intact rock and fracture) has been developed to describe the fracture propagation in a fractured rock. First, this model has been validated against the experimental results and was shown to simulate satisfactorily the fracture propagation in the tensile, shear as well as the mixed (tensile and shear) modes. This model then has been used to investigate the fracture processes during the 2D long-wall mining and 3D pillar failure. According to the 2D and 3D simulations, it was found that: (a) this model can provide a new reasonable approach to simulating fracture processes in either 2D or 3D cases; (b) roof failure is mainly caused by shear fractures rather than tensile fractures during the 2D long-wall mining.