对称采空区下特厚煤层大断面巷道支护研究

Study on Support of Large Cross-section Roadway in Ultra-thick Coal Seam Under Symmetrical Goaf

针对小煤窑开采后,特厚煤层大断面巷道变形破坏严重的问题,采用现场实测和数值模型结合的手段,分析了塔山煤矿1070辅助运输大巷变形破坏特征,提出了"注浆+工字钢支架+锚杆二次支护体系",采用数值模拟手段分析了二次支护效果,并在塔山矿1070辅助运输大巷进行了工程实践。实测表明,二次支护的巷道两帮垂直应力均有一定程度增加,巷道两帮承载能力增强;二次支护的巷道顶板离层仅为原始支护方案的1/11,而巷道侧向位移仅为原始支护方案的1/7,巷道围岩变形得到很好控制。

Aiming at huge deformation and failure problems of large cross-section roadway in ultra-thick coal seam after extracting small coal mine,the deformation and failure characteristics of 1070 auxiliary transportation roadway in Tashan Coal Mine was analyzed by means of field measurement and numerical simulation.The schemes of "grouting+工-type steel support+bolt secondary support system" was put forward.The numerical simulation method was adopted to analyze the effect of the secondary support,and engineering practice was carried out in 1070 auxiliary transportation roadway in Tashan Coal Mine.The field measurement results indicated that a significant increase could be found in vertical stresses and bearing capacity on both sides of the secondary support.The roadway roof separation under the secondary support was 1/11 of that under the original support scheme,and the lateral displacement of the roadway was 1/7 of the original support scheme.It was indicated that the deformation of the roadway surrounding rock was well controlled.