Pre-dig pressure relief chamber technology for roadway rock burst prevention and its application

In response to the frequent roadway rock burst in China and based on the theory of its occurrence, this paper proposed pre-dig pressure relief chamber (PRC) technology and analyzed its dissipation effect on impact energy. In addition, numerical simulation was utilized to investigate the effect of PRC space and depth on relieving roadway surrounding rock stress (SRS). The results are as follows: (I) SRS of original roadway decreases after digging into PRC. The closer to PRC, the greater in stress reduction, and the stress concentration region is transferred to PRC. (2) PRC with smaller space or greater depth can further decrease roadway SRS, meanwhile, the stress concentration region moves toward PRC with the increase of its depth. Field test has demonstrated that PRC can prevent roadway rock burst and pre-dig PRC is one of the most efficient technologies in this aspect.