我国工业体系的稳定运行依赖着煤炭资源，近年来随着东部煤炭资源的枯竭，煤炭生产中心已逐渐转移到中西部地区，煤炭资源需求的增加使得煤炭开采强度变大、开采深度变深，这使得我们需要面临一些诸如动力灾害、水害、煤层自燃和瓦斯突出等开采难题，其中瓦斯突出造成的灾害尤为严重，故在三软煤层矿井开展采空区覆岩裂隙场演化的研究进而来指导瓦斯矿井的瓦斯抽采变得尤为重要。

文章主要采用了物理数值模拟分析方法来确定工作面覆岩裂隙演化规律，结合现场工业实验构建了一个简化的工程模型来指导瓦斯抽采，最后利用数值模拟确定高位钻孔的垂距和平距，近一步指导瓦斯抽采。通过本文的研究发现三软煤层开采覆岩破断特征与非三软煤层开采不同，初次来压较早，初次来压后顶板随采随落，周期来压步距小；通过不同推速下覆岩关键层应力和离层量等的分析得到推速对三软煤层综放覆岩的影响变化规律；现场钻孔窥视和微震监测的结果和模拟实验的结果相一致，最后确定了1508工作面裂隙带高度在65m左右，冒落带高度在18m左右；通过前述分析构建了三软煤层开采的覆岩裂隙采动工程简化模型，瓦斯富集区位移椭抛带中，通过三软煤层卸压瓦斯抽采关键参数数值模拟分析，确定了高位钻孔终孔位置垂距为18~27m，平距为10~25m。

上隅角和回风巷瓦斯浓度在施工高位钻孔抽采瓦斯后均降低到安全范围内，确保了工作面的安全生产，本文研究成果对三软煤层采动覆岩裂隙演化规律、卸压瓦斯抽采关键参数的设计，以及提升瓦斯抽采效率具有重要的指导意义。

The stable operation of my country’s industrial system relies on coal resources. In recent years, coal production centers have gradually moved to the central and western regions with the exhaustion of coal resources in the east. The increase in demand for coal resources has increased the intensity and depth of coal mining. We need to face some mining problems such as dynamic disasters, water disasters, spontaneous combustion of coal seams, and gas outbursts. Among them, the disasters caused by gas outbursts are particularly serious. Therefore, in the three-soft coal seam, the evolution of the overburden fissure field in the goaf is used to guide the gas mine. The gas drainage becomes particularly important.

The article mainly uses the physical numerical simulation analysis method to determine the evolution of the overburden cracks in the working face. Combined with the on-site industrial experiment, a simplified engineering model is constructed to guide the gas drainage. Finally, the numerical simulation is used to determine the vertical and horizontal distances of the high-level boreholes. Take a step closer to guide gas drainage. Through the research of this article, it is found that the overburden failure characteristics of three-soft coal seam mining is different from that of non-three-soft coal seam mining. The initial pressure is earlier, and the roof falls with the mining after the initial pressure. The cycle pressure step is small; under different pushing speeds The analysis of the amount of stress separation in the key rock layers, etc., obtains the influence of the pushing speed on the overlying rock in the three-soft coal seam; the results of on-site drilling and microseismic monitoring are consistent with the results of the simulation experiment, and finally the 1508 working face cracks are determined The height of the belt is about 65m, and the height of the caving zone is about 18m. Based on the foregoing analysis, a simplified model of the overburden crack mining engineering for the mining of the three-soft coal seam is constructed. In the displacement ellipse zone of the gas enrichment zone, the pressure is relieved by the three-soft coal seam. Numerical simulation analysis of the key parameters of drainage has determined that the vertical distance of the final hole position of the high drilling hole is 18~27m, and the horizontal distance is 10~25m.

After the high-location drilling is used to extract the gas, which ensures the safe production of the working face, the phenomenon of gas concentration is reduced to a safe range in the upper corner and the return airway. The research results in this paper have a positive effect on the evolution law of the overburden cracks in the three-soft coal seam and the pressure relief. The design of the key parameters of gas drainage and the improvement of the efficiency of gas drainage have important guiding significance.

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