Impact hazard analysis of islanding face mining based on micro-seismic monitoring and shock wave CT inversion

Abstract Considering the susceptibility of typical isolated working faces to intense ore pressure and the potential for rock burst disasters, this study employs micro-seismic monitoring and shock wave computed tomography (CT) inversion data from the 10304 isolated working face at Xinglongzhuang Coal Mine. The analysis focuses on the structural characteristics of the overburden rock and the evolutionary patterns of impact hazards within the isolated working face. The findings indicate that during mining operations in the vicinity of the cutting eye the irregular coal pillar and the NF6 fault were subjected to mining-induced disturbances, which altered the stress conditions. A clustering of micro-seismic events was observed at the incision location, with events exhibiting energies surpassing 5 × 103 J. The reactivation of the NF6 fault within the 10303 goaf led to the rock fragmentation, resulting in a stress anomaly area within the same goaf. As the working face approached the F3 fault, the fault was influenced by the working face's disturbance, triggering fault activation. This results in extensive roof collapse, compromise of the surrounding rock's integrity, and an increase in the frequency of high-energy micro-seismic events to 756. Concurrently, a high-stress area emerged near the coal pillars on both adjacent sides of the goaf. By integrating micro-seismic monitoring, shock wave CT inversion data, and 3DEC numerical simulation outcomes, the regions of high stress concentration are precisely identified. This integrated approach allows for the assessment of impact risks and provides experience in preventing and controlling rock burst disasters.