富水特厚砂砾岩下采煤覆岩破断特征及采高确定

Fracture Characteristics and Mining Height of Overlying Strataunder Water Rich Extra Thick Sand Conglomerate

为确定干沟煤矿2601工作面受富水特厚砂砾岩影响下的安全采高,综合运用现场实测、理论分析、数值模拟及相似模拟实验的方法,对工作面导水裂隙带高度进行了研究。研究结果表明,干沟煤矿工作面覆岩裂采比实测值为7.5,以裂采比7.5计算了2601工作面在不同采高条件下覆岩的导水裂隙高度,确定了工作面安全采高上限为5.0 m;在设定采高5.0 m条件下,采用数值模拟及相似模拟实验进一步验证得出覆岩破坏高度分别为40.0、37.0 m,与利用裂采比7.5预计的结果相近,说明2601工作面采煤高度确定为5.0 m是可行的。

In order to determine the safe mining height of2601working face in Gangou Coal Mine under the influence of water rich extra thick sand conglomerate,the height of hydraulic fracture zone of the working face was studied by using the method of field measurement,theoretical analysis,numerical simulation and similar simulation experiment.The results show that the measured split ratio of overlying strata of the working face in Gangou Coal Mine is7.5,the hydraulic fracture height of the overlying strata of2601working face under different mining heights is calculated with the split ratio7.5,and the upper limit of the safe mining height of the working face is set as5.0m;under the condition of set mining height of5.0m,numerical simulation and similar simulation experiments are used to further verify that the overlying strata failure height is40.0m and37.0m respectively,the result is similar to that predicted by using the split ratio of7.5,indicating that it is feasible to determine the mining height of2601working face as5.0m.