Stability control of roadways under residual coal pillars in close-distance coal seams considering synclinal tectonic stress
摘要
In response to the complex in-situ stress environment and intense mining pressure in roadways adjacent to residual coal pillars in deep mines, this study takes the 4301 working face of Dongtan Coal Mine as the engineering background. The stress evolution characteristics, surrounding rock deformation laws, and stability control technology of the roadway were systematically investigated using mechanical analysis, numerical simulation, and field monitoring. The results indicate that residual coal pillars induce significant stress concentration in the underlying coal seam roadway. Under the coupling effect of residual coal pillar stress and synclinal tectonic stress, the maximum surrounding rock stress of the roadway reaches 25.2 MPa. Field comparative tests were conducted to optimize the support scheme. The results demonstrate that the full anchor cable support scheme effectively constrains surrounding rock deformation, reducing the maximum roof and rib deformations by 75.5% and 43.5%, respectively, compared with the alternating bolt-cable support scheme. The research findings provide a scientific basis and engineering reference for the stability control of roadways affected by residual coal pillars in deep close-distance coal seams.