Study on the dynamic response mechanism and support control of anchored surrounding rock in deep dynamic-pressure roadways

To address the deformation and instability problems of deep coal mine roadways subjected to strong mining-induced disturbances, this study investigates the reinforcement mechanism and parameter optimization of rock bolt support, taking the −650 m level main return airway of the south wing of Yangcheng Coal Mine as the engineering background. Based on field investigations and microseismic monitoring, the dynamic response characteristics of the roadway under mining disturbances are identified, and the evolution characteristics of stress concentration and energy accumulation in the surrounding rock are clarified, indicating that the roadway exhibits typical impact-prone behavior. Combined with dynamic loading experiments, the anti-disturbance capacity of the surrounding rock is quantitatively evaluated, and the disturbance loading conditions used in numerical simulation are determined. Numerical simulations are further conducted to analyze the influence of bolt length, anchorage length and prestress on the stress distribution, energy evolution and deformation characteristics of surrounding rock. The results show that increasing bolt length promotes the transfer of high-stress zones to deeper regions and reduces the degree of energy concentration. Increasing anchorage length and prestress enhances the constraint effect of the bolting system, suppresses the expansion of the plastic zone, and improves the overall stability of the roadway. Based on these findings, an optimized bolt parameter scheme suitable for deep impact-prone roadways is proposed and validated through field monitoring. The results provide theoretical support for the design of roadway support and the prevention and control of dynamic disasters in deep coal mines.