Numerical simulation of rock bursts triggered by blasting disturbance for deep-buried tunnels in jointed rock masses

Abstract

Frequent dynamic disturbances, such as explosions, vibrations, and earthquakes, may trigger the risk of rock burst disasters around neighbouring deep-buried tunnels. In this study, the PFC software was used to simulate rock bursts triggered by blasting stress waves (dynamic disturbance) to determine their effects on deep-buried tunnels in jointed rock masses. This study investigated the effects of different ground stress values and joint angles on rock bursts in tunnels under intense dynamic disturbance. An analysis of different ground stress values and joint angles revealed the changes in the ejection velocities of damaged rocks and kinetic energy under intense dynamic disturbance. The results show that higher ground stress can alter the proportion of stress waves converted into strain energy and kinetic energy. Joint angles affect the location of the rock burst. The closer the joint angle is to 90°, the greater the damage to surrounding rocks caused by stress waves. Higher ground stress and joint angles increase the risk and intensity of rock bursts, causing significant damage to surrounding rocks, which makes existing tunnels more vulnerable to impact. The findings of this research have important guiding significance to ensure the secure protection of tunnels against rock bursts.