近距离煤层下位工作面巷道支护优化设计

Optimal Design of Roadway Support for Working Faces Down Close to the Coal Seam

长榆河煤矿现开采15号煤与15号下煤层的层间距在0.5~10.6m,属近距离煤层开采,这使得下部煤层开采容易出现矿山压力集中的现象。通过建立相应的数值模型并进行数值模拟。分析了上煤层开采遗留煤柱的影响,发现15号下煤层102工作面回采巷道与遗留煤柱边缘的最优错距为20m。当层间距<2.5m时,采用11号工字钢棚+斜撑+金属网支护;当层间距在2.5~8m时,采用11号工字钢棚+锚杆+科撑+金属网支护;当层间距>8m时,巷道为矩形巷道,采用锚杆+金属网+钢筋梁+锚索补强联合支护。

The seam spacing between No. 15 coal and No. 15 lower coal seam of Changyuhe coal mine is 0.5~10.6 m which is a close seam mining, which makes the lower coal seam mining prone to the phenomenon of mine pressure concentration. By establishing the corresponding numerical model and conducting numerical simulation, the influence of the coal pillar left behind by the upper coal seam mining was analysed. The optimal staggered distance between the return roadway and the edge of the leftover coal pillar was found to be 20 m. When the layer spacing was <2.5, No. 11 I-beam shed + diagonal bracing + metal mesh support was used. When the layer spacing is between 2.5 and 8 m, No. 11 I-beam shed + anchor + diagonal bracing + metal mesh support is used. When the layer spacing is >8 m,the roadway is rectangular in shape and is supported by a combination of anchor bar + metal mesh + reinforcing beam + anchor cable reinforcement.