Propagation Law of Stress Wave and Cracks in Non-penetrating Jointed Rock Mass: A Numerical Study Based on Particle Flow Code

It is important to study the interaction between stress wave propagation and rock joints to prevent dynamic disasters in rock mass engineering. In this manuscript, the numerical SHPB system and sandstone rock model were established firstly and then considering different joint vertical and horizontal distance analyzed the propagation law of stress wave and cracks. The research results show that the vertical and horizontal distance of the joints affect the waveform, rise time, wave coefficient of the transmitted and reflected stress wave when compared with the intact rock specimens. The crack propagation process can be divided into three stages. Under the influence of the joint vertical distance, the cracks spread like a “circle” and with the increase of the joint vertical distance, the size of the crack “circle” increases. Besides, there are some cracks spread like a “circle” within a certain horizontal distance with the vertical distance fixed. However, with the increase of the horizontal distance, the circle shape of the cracks change into a slanted crack strip when beyond a certain horizontal distance.