Abstract:
To address the issues of excessive surrounding rock deformation and severe damage in the kilometer-long uphill roadway of panel Ⅲ3 in Zhuxianzhuang Coal Mine, which have adversely affected safe production, we systematically analyzed the geological conditions, hydrogeological characteristics, and development layout of the research area. On this basis, an engineering geological model for deep kilometer-long roadway surrounding rock development was established through field investigations. Using numerical simulation methods, the deformation and failure characteristics as well as the instability mechanism of the surrounding rock of the deep uphill roadway under the initial support scheme were studied. Aiming at the deficiencies of the initial support, a secondary optimized support scheme incorporating grouted anchor bolts, anchor cables, and steel strips was proposed, and the differences in surrounding rock deformation and failure before and after the two support schemes were compared and analyzed. The research results show that under the initial support conditions, the maximum roof subsidence of the roadway reaches 16.6 cm, the maximum floor heave is approximately 12.7 cm, and the maximum depth of surrounding rock failure is 1.5 m; when the excavation advanced reaches 6-8 m, its influence on the surrounding rock monitoring section at the initial position of 2 m is significantly weakened. Based on these findings, a secondary optimized support control technology for deep roadway surrounding rock was proposed. Numerical simulation was adopted for inversion verification, the result shows that after the secondary optimized support, the surrounding rock displacement, stress distribution, and anchor bolt force state are significantly improved over a wide range. Among these improvements, the axial force distribution of the anchor bolts is more uniform, and the maximum value is significantly reduced, which effectively enhances the safety and reliability of the anchor bolt support. A comparison of the quantitative data of the in-situ displacement field and stress field before and after the two support schemes reveals that the monitoring laws of the two support methods at the fixed monitoring section are in good consistency. However, after the secondary optimized support, the influence range of surrounding rock displacement is significantly reduced, the compressive stress on the two sidewalls is remarkably decreased, no tensile stress occurs in the roof and floor, and the surrounding rock stress distribution tends to be more reasonable. Field investigations further confirm that no obvious deformation or failure of the surrounding rock occurs after the secondary optimized support, indicating that this scheme has a significant control effect on the surrounding rock of deep roadways.