Asymmetric deformation mechanism of mining roadways and unloading and supporting integrated full-space support technology

ZHOU Bo; ZHOU Ze; XU Youlin; LI Peng; ZHANG Chuanjiu; LI Xuanliang

doi:10.13347/j.cnki.mkaq.20250435

Abstract：Aiming at the problems such as asymmetric deformation of deep close distance coal seams mining roadway,taking the close distance coal seam dynamic pressure roadways of 1640 and 1620 railway transportation lanes in a coal mine as the engineering background,field investigations,theoretical derivations and numerical simulations were carried out.The causes of the asymmetric deformation and failure of the roadways were analyzed.It was found that the mining stress field has a delayed influence on the local stress field of the roadways,resulting in the roadways being in an unbalanced(extremely)high stress field range.This is the funda-mental cause of the asymmetric deformation and failure of the roadways.Based on the principle of stress control,the concept of in-tegrated support technology for unloading and anchoring in the full space was proposed.Through deep-hole blasting,the concen-trated stress formed at the two sides of the roadway was fully released to improve the stress environment of the roadway surrounding rock;at the same time,the full-section steel-concrete pipe support was used to provide full-section support for the roadway surround-ing rock,in order to help the surrounding rock achieve self-stabilization.The anchoring and grouting technology is adopted to rein-force the deep part of the roadway surrounding rock,mobilizing the self-bearing capacity of the deep part of the roadway surround-ing rock,thereby forming two bearing structures,"inside and outside";these two bearing structures cooperate with each other to jointly bear the pressure of the roadway surrounding rock,thereby improving the stability and bearing capacity of the roadway.The results of the underground industrial test show that by implementing the integrated full-space support technology for the dynamic pressure roadway in close-distance coal seams,the self-bearing capacity of the roadway surrounding rock is fully utilized.The de-formation of the roadway surrounding rock due to mining activities is significantly reduced.The maximum deformation of the floor is decreased by 75.83%,and the maximum displacement of the two sides is reduced by 80%.The mining roadway can maintain long-term stability during the advancement of the working face,proving that the integrated full-space support technology can effectively control the asymmetric deformation of the mining roadway in close-distance coal seams.