With increasing coal mining depth, coal bumps-disasters that severely compromise mine safety-have garnered growing attention in the mining industry. Among these, coal bump sliding-type coal bumps cause significant structural damage and pose serious safety hazards. Analysis of damage patterns indicates that such sliding typically originates from insufficient strength at the coal-rock interface. To address this issue, bolt support technology has been proposed to enhance the reinforcing capacity of roadway support systems at this critical interface. The arrangement angle of the bolts significantly affects the reinforcement of the interface. This study uses ABAQUS software to simulate and analyze the stress-strain and bearing characteristics of bolts at support angles of 30°, 45°, 60°, and 90°. The simulation results show that at support angles of 30° and 45°, the bolt fails primarily due to tensile forces, while at 60° and 90°, failure is mainly caused by shear forces. The higher load-carrying capacity of the bolt under tensile damage, compared to shear damage, indicates stronger reinforcement of the interfaces. The research findings were implemented in the return airway of a working face at a coal mine. Field observations during roadway excavation in the test section revealed relatively minimal roof separation. Compared to the conventional support system, the cumulative sidewall displacement was reduced by 28.6% during excavation and by 51.9% after mining commenced, while roof separation remained consistently low. These results confirm that the proposed bolt support technology significantly improves control of the surrounding rock mass in roadways.
Wang et al. (Tue,) studied this question.