关键词: 底板巷道, 采动应力集中, 卸压护巷, 应力转移

Abstract: To solve the difficulties of mining the No.61 coal seam without destroying the overlying main entry in the Qidong coal mine, the methods of theoretical analysis and numerical simulation are adopted to study the mining-stress influence induced by overlying coal seam and surrounding rock movement regularities of the main entry. The research results show that the essential reason of the surrounding rock failure is the transfer of mining-induced stress which caused by the overlying coal seam mining, the stress concentration coefficient increasing to 1.5~1.8 times of the original stress value. The inducing factors of surrounding rock stress concentration and the maintenance principle of roadway pressure-relief should be taken into account in order to control the stability of the main entry underlying the coal seam. Based on the pressure-relief support theory, corresponding measures and technical parameters of the drilling blasting pressure-relief technology are put forward. Simultaneously, the pressure-relief technology is successfully applied to the main entry of Qidong coal mine. Engineering practice results indicate that the plastic weakening regions are interconnected through the drilling blasting. The pressure-relief technology could transfer the concentrated stress to the deeper part of the surrounding rock to reduce the degree of stress concentration. The main entry could keep maintain stability after the necessary pressure-relief measures are performed.