基于微震监测的深埋煤层顶板导水裂隙带发育特征

导水裂隙带发育高度是矿井水害预测的重要技术参数之一。以彬长矿区文家坡煤矿4103工作面为研究对象，利用井-地联合微震监测技术对顶板导水裂隙带发育特征进行研究。研究结果表明：深埋煤层开采时，微震事件超前工作面回采位置发育，超前影响角最大为35°，最小为28°；断层的存在降低了覆岩稳定性，相较于正常基岩，更易在回采影响下发生应力集中和破坏；断层加大了微震事件发生的超前距，而采空区则使微震事件的高密度区向其所在部位发生偏移，加剧覆岩破坏程度，增大导水裂隙带发育高度；垂向上，4103工作面监测区内的微震事件高密度区域主要集中在高程+400~+520 m，结合微震事件数量和能量分布特征，判定4103工作面垮落带发育高度为50 m，垮采比13.16，导水裂隙带发育高度为117 m，裂采比为30.79。该成果可为彬长矿区类似煤矿深埋煤层顶板导水裂隙带发育高度研究及顶板水防治提供重要依据。移动阅读

Development characteristics of water-conducting fractured zone in deep coal seam based on microseismic monitoring

The development height of the water conducting fractured zone is one of the important technical parameters for mine water hazards prediction. In this paper, the combined well-surface microseismic monitoring technology was used to analyze the development characteristics of the water conducting fractured zone in working face 4103 in Wenjiapo coal mine. The results showed that for deep buried coal seams, the microseismic events occured in the advance mining face with advanced influence angle ranging from the minimum of 28° to the maximum of 35°. The stability of overburden decreased due to the faults. Thus, compared with normal bedrock, the overburden rock was easier to cause stress concentration and rock failure under the influence of coal mining. The distance between the microseismic event location and mining position increased affected by the fault, and the high density distribution area of the microseismic events shifted to the goaf, which aggravated the degree of overburden failure and increased the water conducting fractured zone height. In vertical direction, the high density area of microseismic events in the monitoring area of working face 4103 ranged from +400 m to +520 m. Combined with the number and the energy distribution characteristics of microseismic events, it could be concluded that the development height of caving zone in working face 4103 was 50 m, and the ratio of caving to mining was 13.16. The development height of water-conducting fractured zone was 117 m, and the ratio of fracturing to mining was 30.79. The results could provide an important basis for the analysis of water conducting fractured zone height of deep coal seam and the prevention of roof mine water disaster in Binchang mining area.