Dynamic damage constitutive model for persistent jointed rock mass based on combination model method

According to the dynamic deformation characteristics of the persistent jointed rock mass and the relevant results of the existing rock dynamic constitutive models, the dynamic stress of the persistent jointed rock mass is regarded as the summation of two components, which are the static stress and the dynamic stress components respectively. The static stress component of the persistent jointed rock mass is simulated using three basic deformation components connecting in series such as the nonlinear component reflecting the rock mesoscopic damage, joint closure and shear deformation components. The dynamic stress component is simulated using the viscous component. Then the uniaxial dynamic compression damage constitutive model is set up. Next, according to the fact that the persistent jointed rock mass often shears to fail along the joint face under the uniaxial load, the joint shear failure criterion is introduced into the damage constitutive model established above to revise it, which can perfectly consider the effect of the joint shear strength on this model, and the uniaxial compression damage constitutive model of persistent jointed rock mass considering the joint shear strength is established finally. Then this model is adopted to calculate the mechanical properties of the persistent jointed rock mass under compression load, and the effect law of the joint dip angle on the rock mass uniaxial compression dynamic climax strength is especially discussed. The results show that the failure modes of the jointed rock mass