随着我国大部分矿山进入高强开采阶段，煤炭产量不断上升导致瓦斯涌出量增大，造成工作面经常性出现瓦斯异常等事故，直接影响煤炭行业安全生产和绿色发展。本文以山西和顺某高瓦斯矿井主采工作面地质条件为原型，利用物理相似模拟实验及3DEC数值模拟实验，结合分形理论、渗流力学开展了采动卸压瓦斯高渗区演化规律影响因素实验研究，初步得出以下研究结果：

（1）利用采动覆岩裂隙演化物理相似模拟实验台，开展采动卸压瓦斯高渗区几何边界辨识物理相似模拟实验，获得了采动覆岩垮落形态分布、覆岩离层量、表面裂隙率破断裂隙密度及分形维数等特征参数变化特征，基于裂隙网络特征参数建立采动卸压瓦斯高渗区几何边界判定准则，最终获得卸压瓦斯高渗区几何范围及动态演化过程。

（2）通过3DEC数值模拟软件建立不同工作面采高、煤层倾角、工作面回采率及推进速度条件下工作面数值模型，开展数值模拟实验。系统分析了采动过程中工作面上部岩层裂隙产生、扩展、发育、贯通再压实闭合的过程，获得不同开采条件时采空区形态动态分布特征。

（3）利用TECPOLT数据后处理软件监测不同条件下工作面采动后岩层下沉量及应力变化规律，基于渗透系数理论计算方法，获得不同影响因素工作面渗透系数变化规律。结合高渗区采动过程中应力分布特征，进一步分析了采场上覆岩层变形破坏过程中应力变化与渗透系数的演化关系，得出工作面采高变化对覆岩渗透性影响最大，最大渗透系数随采高增大分别为0.56m/s、2.02m/s、10.06m/s和24.7m/s。

（4）基于试验矿井主采工作面开展瓦斯抽采试验。得出：钻孔平均抽采瓦斯浓度随着垂距增加逐渐增大。当垂距由7.94m上升到17.92m时，高渗区内钻孔平均抽采瓦斯浓度为44.82%，冒落带内钻孔瓦斯抽采浓度为10.34%，钻孔瓦斯抽采浓度增大了4.3倍，将试验结果推广至新疆某高瓦斯矿井倾斜工作面取得良好的抽采效果。

通过上述研究，本文利用覆岩裂隙网络特征参数确定采动卸压瓦斯高渗区几何范围，运用数值模拟实验获得了不同影响因素工作面采动卸压瓦斯高渗区岩层下沉、应力变化及渗透系数演化规律，对矿井瓦斯抽采技术及灾害防控等现场实际问题提供了重要的理论支撑。

In recent years, as most of China's mines enter the stage of high-strength mining, the increasing coal output leads to the increase of gas emission, resulting in frequent gas anomalies and other accidents in the working face, which directly affects the safe production and green development of the coal industry. Based on the geological conditions of the main mining face of a high gas mine in Heshun, Shanxi Province, this paper carried out an experimental study on the influencing factors of the evolution law of the high permeability area of mining pressure relief gas by physical similarity simulation experiment and 3DEC numerical simulation experiment, combined with fractal theory and seepage mechanics, and obtained the following preliminary results:

(1) Physical similarity simulation experiment of geometric boundary identification of mining-induced pressure relief gas hyperpermeability zone was carried out by using physical similarity simulation experiment platform of mining-induced overburden fracture evolution, and the variation characteristics of characteristic parameters of mining-induced overburden fracture morphology distribution, overburden layer separation amount, surface fracture rate fracture density and fractal dimension were obtained. Based on the characteristic parameters of the fracture network, the geometric boundary criterion of the hyperpermeability zone of the pressure relief gas was established, and the geometric range and dynamic evolution process of the hyperpermeability zone of the pressure relief gas were finally obtained.

(2) Through 3DEC numerical simulation software, the working face numerical model was established under the conditions of different working face mining height, coal seam dip Angle, working face recovery rate and propulsion speed, and the numerical simulation experiment was carried out. The process of formation, expansion, development, connection and then compaction and closure of rock fissures in the upper part of working face during mining is systematically analyzed, and the dynamic distribution characteristics of goaf form under different mining conditions are obtained.

(3) The TECPOLT data post-processing software was used to monitor the strata subsidence and stress variation of working face after mining under different conditions. Based on permeability coefficient theoretical calculation method, permeability coefficient variation rule of working face with different influencing factors was obtained. Combined with the stress distribution characteristics in the process of mining in high permeability area, the evolution relationship between stress change and permeability coefficient in the process of deformation and failure of overlying strata was further analyzed. It was concluded that the change of working face mining height had the greatest influence on the permeability of overlying strata, and the maximum permeability coefficient was 0.56m/s, 2.02m/s, 10.06m/s and 24.7m/s with the increase of mining height.

(4) Carry out gas extraction test based on the main mining face of the test mine. The results show that the average gas concentration increases with the increase of vertical distance. When the vertical distance increases from 7.94m to 17.92m, the average gas extraction concentration of boreholes in the high permeability area is 44.82%, and that of boreholes in the caving zone is 10.34%, and the gas extraction concentration of boreholes increases by 4.3 times. The experimental results are extended to the inclined working face of a high gas mine in Xinjiang and good drainage effect is achieved.

Through the above research, the characteristic parameters of strata fracture network is used to determine the scope of gas mining in high permeability zone geometry, with the use of numerical simulation to obtain the different factors affecting the working face gas mining in high permeability zone coefficient of permeability of strata subsidence, stress variation and evolution, and disaster prevention and control of mine gas extraction technology such as field practical problems provides an important theoretical support.