板集煤矿导水裂隙带发育高度研究

Study on development height of water-conducting fracture zone in Banji Coal Mine

板集煤矿110504工作面平均煤层厚度6.1m,属于厚煤层开采,上覆平均厚度约1.6m和75m处存在含水层,矿井安全生产受顶板含水层威胁严重,亟需开展导水裂隙带发育高度研究。本文开展数值模拟研究了覆岩裂隙演化规律,通过运用UDEC 7.0软件建立开采模型描述工作面推进过程中的导水裂隙带演化规律,得出工作面推进至50m时直接顶开始垮落,推进至70m时直接顶完全垮落、基本顶部分垮落,推进至140m时形成了明显的垮落带和裂缝带区域,推进至190 m时导水裂隙带高度达到最大值66 m,垮落带高度23 m,裂缝带高度43 m;开展了电法测试,运用网络并行电法在110504工作面轨道顺槽内进行现场实测,得出工作面应力超前影响距最大为58 m,裂缝角为69.62°,导水裂隙带最大高度73 m,垮落带高度27m,裂缝带高度46m。数值模拟结果与电法测试结果基本一致,研究成果对相似地质条件下的导水裂隙带高度研究具有重要意义。

The 110504 working face in Banji Coal Mine with an average coal seam thickness of 6.1 m is a thick coal seam,above which has two water horizons at 1.6 m and 75 m.The overlying water horizons seriously affects the safety of mine production,and it is urgent to carry out the research on the development height of water conducting fissure zone.In this paper,UDEC 7.0 software is used to establish the mining model of 110504 working face and to simulate the evolution of water conducting fissure zone in the process of mining.The simulation results show that the immediate roof began to collapse when the working face advances to 50 m,and completely collapsed at 70 m.When it advances to 140 m,obvious caving zone and fracture zone are formed.When it advances to 190 m,the height of water conducting fissure zone reaches the maximum of 66 m,caving zone is 23 m,and fracture zone is 43 m.In addition,the network parallel electrical method is used in the head gate of 110504 working face.The field monitoring data show that the maximum influence distance of the abutment pressure is 58 m,the crack angle is 69.62°,the maximum height of the water conducting fissure zone is 73 m,the height of the caving zone is 27 m,and the height of the fracture zone is 46 m.The numerical simulation results are basically consistent with the electrical test results.The research results are of great significance to the study of the height of water conducting fracture zone under similar geological conditions.