深埋特厚煤层综放开采覆岩导水裂缝带发育特征

以大佛寺煤矿为试验矿井,采用钻孔电视系统和钻孔简易水文观测法,探测深埋特厚煤层综放开采顶板导水裂缝带发育高度,并对导水裂缝带演化特征进行相似模拟和数值模拟试验研究。研究分析表明:大佛寺煤矿深埋特厚煤层综放开采顶板导水裂缝带发育高度为170.80~192.12 m;裂缝带区域内,裂隙数量自上而下逐渐增多,近煤层区域裂隙异常发育;钻孔砂岩区域,受拉伸作用,形成了纵横交错的裂隙,裂隙尺寸、角度较大;工作面回采距离与顶板导水缝隙带发育高度曲线呈"台阶"型。

Development characteristics of water flowing fractured zone of overburden deep buried extra thick coal seam and fully-mechanized caving mining

At Dafosi Coal Mine，a borehole televiewer system and a borehole flushing fluid leakage method were used to monitor the height of water flowing fractured zone of overburden in a deep buried extra thick coal seam fully-mechanized caving mining face.Also，a similarity simulation experiment and a numerical simulation experiment on the development characteristics of water flowing fractured zone were conducted.The research results show that：① The height of water flowing fractured zone of overburden in a deep buried extra thick coal seam fully-mechanized caving mining face at Dafosi Coal Mine is from 170.80 m to 192.12 m.② In fractured zone，the number of fissures increases from top to bottom，the fissures near coal seam zone are well developed.③ In sandstone zone，due to tension effect，the fissure of criss-cross is mainly with high dimension and high angle.④ The curves of mining distance and the height of water flowing fractured zone is step-shaped.