Numerical simulation on influence of mesoscopic heterogeneity on macroscopic behavior of rock failure

A newly developed numerical method, RFPA 2D ,used for analysis of rock failure process is applied to study the influence of mesoscopic heterogeneity on macroscopic behavior of rock failure. The failure procedures of rock sample with various kinds of heterogeneity are simulated.The results show that the nonlinear behaviour of rock deformation and fracture pattern are more pronounced in more heterogeneous cases than in homogeneous cases. With increase in the degree of rock homogeneity the macroscopic strength of rock rises following exponent function, macroscopic linearity becomes more obvious,and the macroscopic failure process presents markedly brittle behavior. The numerical tests on 10 samples with same homogeneity index show that the deformation and failure behavior before reaching the maximum strength is nearly the same but varies greatly during the unstable failure process.