A crater blasting model of rock with pre-existing defects, including voids,pores and small open joints,under blasting loads was established,based on experiment results.The defects were randomly distributed,and empty or saturated with water.A shock equation of state (EOS),obtained from the existing test results,was employed for the granite near the explosive charge,meanwhile for the granite far from the charge,a linear EOS was applied.A modified principal stress failure criterion was applied to determine the granite statuses.The granite dynamic strengths,which increase with strain rate,were calculated from the existing test results.The simulation results showed that under blasting,for the rock with water inside defects, the strength decrease,and the larger the defect density is,the smaller the damage range is.Finally, the effect of blasting on tunnel stability was discussed.
