Study on influence of initial crack dip angle on damage-fractured characteristics of rock

In order to discuss on impacts of initial crack dip angle on damage-fractured characteristics of rock, the damage-fractured process of rock with a single C rack under uniaxial compression was simulated using numerical test of rock failure RFPA. Five samples with different crack dip angle were used. The influence of initial crack dip angle on crack propagation direction and fracture direction in rock was analyzed according to stress images of different loading steps. Redistribution laws of i nternal stress of rock were obtained. It was divided into three stages such as damage initiation and stable growth stage, damage rapid expansion and connection stage and rock failure stage with the change of AE count. Results showed that stress values in rock increased linearly on the stage of damage initiation and stable growth. Th e maximum values of maximum principal stress and maximum shear stress increased most rapidly when the initial crack dip angle was 45°. The maximum value of mini mum principal stress increased most rapidly when the initial crack dip angle was 15°.