极近距离煤层群下煤层开采巷道支护技术研究

Research on roadway support technology of lower coal seam mining in extremely close distance coal seam group

极近距离煤层群开采导致下煤层顶板破坏严重,支护难度增大。为了研究下煤层巷道顶板支护最佳方案,以甘庄煤矿11和14号煤层开采为背景,通过岩石力学实验、现场窥视和理论计算得到了巷道的理论支护方案,采用数值模拟的方法对理论支护参数进行模拟分析,并在现场展开监测。研究表明,14号煤层理论计算支护参数为锚杆φ18 mm×2 000 mm的螺纹钢,间排距1 200 mm×1 100 mm;锚索φ15.24 mm×4 000 mm的钢绞线,间排距为2 400mm×1 100 mm,根据巷道垂直应力和垂直位移云图得到最优支护方案,并进行现场监测验证。该研究为后续巷道的支护提供了理论依据,并为类似地质条件提供了一种解决方案。

The mining of extremely close distance coal seam group leads to serious damage of the lower coal seam roof,which increases the difficulty of supporting.In order to study the optimal solution of roof support in lower coal seam roadway,the mining of No.11 and No.14 coal seams in Ganzhuang Coal Mine was taken as the background,the theoretical support scheme of roadway was obtained through rock mechanics experiment,field peep and theoretical calculation.The theoretical support parameters were simulated and analyzed by numerical simulation,and the monitoring was carried out on site.The research showed that the theoretical calculation support parameters of No.14 coal seam are boltφ18 mm×2000 mm rebar,row spacing 1.2 m×1.1 m;cableφ15.24 mm×4000 mm steel strand,spacing of 2.4 m×1.1 m,obtained by the vertical stress and vertical displacement of the roadway cloud support program(b)was the optimal support program,and verified by field monitoring.This study provided a theoretical basis for the support of subsequent roadways in the mine,and provided a solution for similar geological conditions.