断层影响下弱胶结软岩工作面停采线合理位置确定

Determination of Reasonable Stopping Line Position in Weakly Cemented Soft Rock Face under Influence of Fault

弱胶结软岩条件下的高地应力矿井,尤其是受断层影响时,停采线位置对工作面停采后撤架工作及井下安全影响显著。以某矿11302综采工作面为工程背景,采用数值模拟和现场监测,通过模拟断层附近能量分布,现场实测确定工作面超前支承压力影响范围,最终确定合理停采线位置。结果表明:由FLAC^(3D)模拟获取无采动影响时断层附近煤层内能量聚集区域为8 m;模拟工作面推采过程副撤架巷围岩能量变化,初步获得停采线可设置在距副撤架巷大于124 m或80~116 m内;结合超前单柱受力及钻孔应力数据变化确定工作面超前影响范围约90 m。考虑经济及安全因素,确定停采线距副撤架巷99 m,对副撤架巷表面位移连续监测,变形量均在150 mm范围内,无明显底鼓等矿压显现现象,现场应用效果良好。

Under the condition of weak cemented soft rock, especially under the influence of faults, the position of stopping line has a significant impact on the withdrawal of support after stopping and underground safety. Taking 11302 fully mechanized mining face of a mine as the engineering background, using numerical simulation and field monitoring, through simulating the energy distribution near the fault, the influence range of advance bearing pressure of the working face is determined through field measurement, and finally the reasonable stopping line position is determined. The results show that the energy accumulation area in the coal seam near the fault is 8 m when there is no mining influence obtained by FLAC^(3D)simulation;by simulating the energy change of surrounding rock of auxiliary frame removal roadway in the push mining process of working face, it is preliminarily obtained that the stopping line can be set within the range of more than 124 m or 80-116 m from the auxiliary frame removal roadway;combined with the stress of the leading single column and the change of drilling stress data, the leading influence range of the working face is determined to be about 90 m.Considering economic and safety factors, it is determined that the stopping line is 99 m away from the auxiliary frame removal roadway. The surface displacement of the auxiliary frame removal roadway is continuously monitored, and the deformation is within 150 mm. There is no obvious ground pressure phenomenon such as floor heave, and the field application effect is good.