地表水体下工作面开采安全性分析

为了避免大采高工作面重复开采沟通至地表水体,发生水害事故,采用关键层理论及相似材料模拟对工作面覆岩破坏规律进行了研究。基于关键层理论,确定了红石湾煤矿五煤及八煤覆岩中的关键层,并计算了导水裂隙带发育高度;根据煤层覆岩物理力学参数及地质条件,建立了相似材料物理模型,分别模拟了五煤开采、五煤和八煤开采条件下覆岩破坏高度。结合研究区构造发育条件及隔水层的隔水性能,核算了水体下防隔水煤(岩)柱的留设,明确了五煤和八煤开采不受地表水体的威胁。研究结果表明:对于大采高工作面重复开采条件下的覆岩破坏高度,经验公式并不适用,可以采用关键层理论及相似材料模拟来确定导水裂隙带发育高度。通过实例验证,对地表水体下工作面开采的安全性评价是科学合理的。

Simulation analysis of similar materials for mining safety of working face under surface water

In order to avoid the water disaster under the condition of large height mining working face repeat mining affect to surface water，the failure law of overlying was studied by key stratum theory and similar material simulation.Based on the key stratum theory，the key strarum of No.5 coal and No.8 coal were determined in Hongshiwan Coal Mine，and the development height of water flowing fractured zone was calculated.According to the physical and mechanical parameters and geological conditions of coal seam overlying，the physical model of similar material simulation was established，and the overlying failure height of No.5 coal，No.5 coal and No.8 coal were simulated respectively.Combined with the tectonic conditions and the water-proof property of aquiclude in the research area，water-proof coal（rock） pillar was calculated，and make it clear that No.5 coal and No.8 coal are not threatened by the surface water.The results showed that ，the empirical formula is not applicable to get the overlying failure height under the condition of large mining height working face repeated mining，the key stratum theory and similar material simulation can be used to determine the height of water flowing fractured zone.Through the example verification，the safety evaluation of working face under the surface water is scientific and reasonable.