综采一次采全高覆岩导水裂缝带高度综合探测及其演化分析

为了保证煤矿的安全生产，采用钻孔冲洗液漏失量观测和钻孔彩色电视系统2种方法，对何家塔煤矿5-2煤层采后不同时期覆岩导水裂缝带高度特征进行了综合探测；同时开展了厚煤层分层开采及厚煤层放顶煤开采统计公式法与实测结果的差异性特征分析及其适应性论述；并对采后不同时期覆岩破坏裂缝带高度演化特征进行了分析。研究结果表明:何家塔煤矿5^-2煤层采后覆岩破坏导水裂缝带高度为74.33 m，裂采比为21.24。厚煤层分层开采公式法和厚煤层放顶煤公式法计算结果与综合探测法实测结果相对误差分别为36.23%和7.62%。在没有现场实测数据的前提下，研究区覆岩破坏导水裂缝带高度可参考厚煤层放顶煤开采公式计算。停采时间相对较短情况下，覆岩导水裂缝带高度发育较大，裂缝规模较为明显，随着停采时间的推移，由于压实作用，覆岩导水裂缝高度会逐渐降低，裂缝规模逐渐减小。

Comprehensive detection and evolution analysis of height of overburden water flowing fracture zone in fully-mechanized mining at one time

In order to ensure the safe production of coal mine，the height of overburden fracture zone in different periods after mining of 5^-2 coal seam in Hejiata Coal Mine was comprehensively detected by using borehole flushing fluid leakage observation and borehole color televiewer system methods.In addition，the differences between the statistical formula method and the comprehensive measurement results of thick seam slicing mining and thick seam top coal caving mining were comprehensively compared and analyzed.Moreover，the height evolution characteristics of overburden fracture zone in different periods after mining were analyzed.The research results showed that:after mining，the overburden fracture height of No.5-2 coal seam in Hejiata Coal Mine was 74.33 m，and the fracture mining ratio was 21.24.The relative errors between the calculation results of the empirical formula methods for thick seam slicing mining and the thick seam top coal caving mining and the detection results of comprehensive measurement method were 36.23% and 7.62% respectively.In the absence of field measured data，the height of fracture in the study area can be calculated by referring to the formular of thick seam top coal caving mining.In the case of short time after coal mining，the height of water flowing fracture zone was larger and the fracture scale was more obvious.However，with the lapse of coal seam stoppage time，the fracture height of overburden rock will gradually decrease after mining，and the fracture scale will gradually decrease and tend to be compacted.