梁北煤矿沿空煤体瓦斯参数和应力分布规律研究

发布时间：2018-07-12 09:05

本文选题：沿空掘巷 + 瓦斯参数　；参考：《中国矿业大学》2017年硕士论文

【摘要】：梁北煤矿具有开采深度大、煤层松软、煤层厚度大、瓦斯含量高等特点,其11131工作面为孤岛工作面,顺槽巷道采用沿空掘巷。沿空掘巷期间如何采取综合防突措施,特别是是否需要采取区域防治措施,取决于沿空煤体内应力和瓦斯参数大小及其分布情况。本文采用理论分析、数值模拟和现场测试验证相结合的方法,对11131工作面沿空掘进巷道掘进前后应力和瓦斯参数分布规律进行研究。1)在沿空巷道掘巷前对沿空煤体瓦斯含量进行了测试,利用朗格缪尔公式计算出瓦斯压力,并分析了两者的分布规律,研究表明:距巷帮18m范围内,沿空煤体瓦斯含量小于6m3/t,瓦斯压力小于0.5MPa;沿空巷道掘巷后对实体煤内钻屑量、钻屑瓦斯解吸指标、瓦斯含量等参数进行了现场测试,分析了其分布规律,结果表明:巷帮20m范围内煤体的瓦斯参数基本上随深度逐渐增大,但未达到或超过防突预测临界值。2)在沿空巷道实体煤内安装应力监测传感器,对采动应力进行了实时监测,并分析了采动应力随时间和距掘进迎头距离变化趋势,结果表明煤体内部高应力区位于距巷帮15m以里的区域内,且机巷煤体整体应力大于风巷;借助FLAC-3D软件,建立11131孤岛工作面三维数值计算模型,研究了沿空掘巷前后煤体的应力分布特征及变化规律,对沿空煤体内应力分布规律进行了数值模拟,研究表明:实测应力变化趋势与数值模拟吻合,即距巷帮15m范围内,垂直应力不断增大。3)对沿空煤体瓦斯参数与实测应力间的相关性进行了研究,结果表明:沿空煤体内瓦斯参数变化趋势和应力呈正相关,这与理论分析一致。4)根据沿空煤体不同位置的瓦斯参数及应力分布规律,分析了巷道内不同区域沿空煤体卸压范围、瓦斯排放效果及沿空掘巷煤体的稳定性和安全性,结果表明:沿空巷道实体煤侧15m范围内应力和瓦斯参数大小及其分布情况符合《防治煤与瓦斯突出规定》。研究结果揭示沿空煤体应力和瓦斯参数分布规律,为后续沿空掘巷顺利进行提供理论依据,同时还能为类似工程提供参考。
[Abstract]:Liangbei coal mine is characterized by large mining depth, soft coal seam, large thickness of coal seam and high gas content. The 11131 face is an island working face, and the roadway along the channel is driven along the goaf. How to take comprehensive measures to prevent outburst during gob excavation, especially whether it is necessary to take regional prevention measures, depends on the size and distribution of stress and gas parameters along goaf coal body. In this paper, theoretical analysis, numerical simulation and field test verification are combined. This paper studies the distribution of stress and gas parameters before and after driving along goaf roadway in 11131 face. 1) the gas content of coal body along goaf is measured before driving roadway along goaf, and the gas pressure is calculated by Langmuir formula. The results show that the gas content of goaf coal is less than 6m3 / t, the gas pressure is less than 0.5MPa, the amount of debris drilling in solid coal is less than 0.5MPa, and the gas desorption index of coal is obtained after digging roadway along the goaf, and the results show that the gas content of coal along goaf is less than 6 m ~ 3 / t and the gas pressure is less than 0.5 MPA. The gas content and other parameters are tested on the spot, and the distribution law is analyzed. The results show that the gas parameters of coal body increase gradually with the depth of the roadway side in the range of 20m. However, the critical value of outburst prevention prediction is not reached or exceeded (.2) the stress monitoring sensor is installed in the solid coal along the goaf to monitor the mining stress in real time, and the trend of the change of the mining stress with time and the head-on distance from the tunneling is analyzed. The results show that the high stress area of coal body is located in the area 15m from the side of roadway, and the overall stress of coal body in machine roadway is greater than that of wind roadway, and the 3D numerical calculation model of 11131 islanding face is established with the help of FLAC-3D software. The stress distribution characteristics and variation law of coal body before and after goaf excavation are studied, and the stress distribution law of coal body along goaf is numerically simulated. The results show that the change trend of measured stress is consistent with that of numerical simulation, that is, within 15 m from the side of roadway, The correlation between the gas parameters along the goaf and the measured stress is studied. The results show that the variation trend of gas parameters along the goaf is positively correlated with the stress. This is consistent with the theoretical analysis .4) according to the gas parameters and stress distribution law of different positions along the goaf coal body, the pressure relief range, the gas drainage effect and the stability and safety of the coal body along the goaf roadway in different areas of the roadway are analyzed. The results show that the stress and gas parameter size and their distribution in the coal side of the goaf meet the regulation of preventing coal and gas outburst. The results reveal the distribution of stress and gas parameters along the goaf, which provides a theoretical basis for the smooth roadway driving along the goaf, and also provides a reference for similar projects.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD712

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