东沟煤矿浅埋煤层群采空区下巷道最佳布置

Optimal layout of roadway under goaf of shallow coal seam group in Donggou Coal Mine

为研究近距离浅埋煤层开采时下位煤层巷道布置方式及合理错距,以新疆东沟煤矿为工程背景,利用FLAC3D数值模拟方法,开展了内错、外错、垂直错层位布置方式的模拟;对比分析了上位煤层开采后,残留煤柱对下位煤层应力分布的影响,以及不同错距下垂直应力分布、塑性区分布规律。研究结果表明:单考虑上位煤层残留煤柱底板应力传播的影响,B_(3)煤层回采巷道采取垂直错、内错距4~16 m时,均可减轻下位巷道矿压显现,避免巷道产生过大变形;综合应力分布、塑性变形、经济效益因素,B_(3)煤层采用垂直错时,可保障巷道稳定性,采出率、经济效益最高,为最优方案。工程实测结果表明:垂直错布置方式下,巷道两帮移近量为23~185 mm,顶底板移近量仅为12~85 mm。

In order to study the roadway layout and reasonable staggered distance of the lower coal seam during the mining of short-range shallow coal seam,taking Xinjiang Donggou Coal Mine as the engineering background,the simulation of the layout of internal,external and vertical staggered layers is carried out by using FLAC3Dnumerical simulation method,and the influence of residual coal pillar on the stress distribution of the lower coal seam after the mining of the upper coal seam is compared and analyzed,as well as the distribution law of vertical stress and plastic zone under different staggered distance.The results show that:considering the influence of residual coal pillar floor stress propagation in the upper coal seam,when the mining roadway of B_(3)coal seam adopts vertical staggered and internal staggered distance of 4-16 m,the mining pressure of the lower roadway can be reduced and excessive deformation of the roadway can be avoided;considering the factors of stress distribution,plastic deformation and economic benefit,the vertical staggered time in B_(3)coal seam can ensure the stability of roadway,and the recovery rate and economic benefit are the highest,which is the best scheme;the engineering measurement results show that under the vertical staggered arrangement,the approach of the two sides of the roadway is 23-185 mm,and the approach of the roof and floor is only12-85 mm.