保护层开采防突效果区域时空演化规律研究
Study on Spatiotemporal Evolution Laws of Anti-outburst Effect Area of Upper Protective Layer Mining
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摘要: 在煤层群开采中,利用保护层采动作用产生的“卸压增透”效应来提高煤层透气性是最具有效的措施。基于理论分析结合数值模拟的方法,研究贵州某矿区上保护层开采后,伏岩应力、应变的区域时空分布规律。结果表明:开采保护层后,伏岩区域存在应力集中区、过渡区和卸压区,根据建立的方程得出卸压区最大变形量为82.7 mm;伏岩部分区域应力(变)及变形量随着保护层开采有所恢复,表明区域增透卸压效果存在时效性和空间差异性;模拟伏岩最大变形量为80 mm,与理论计算结果基本一致。Abstract: In the mining of coal seam group, it is the most effective measure to improve the permeability of coal seam by utilizing the effect of “pressure relief and permeability improvement” produced by mining in protective layer. Based on the method of theoretical analysis and numerical simulation, this paper studies the spatial and temporal distribution of the stress and strain of the rock in Guizhou Mining Area. The results show that there are stress concentration zone, transition zone and pressure relief zone after mining protective seam; and the maximum deformation amount of the pressure relief zone is 82.7 mm according to the established equation. It is restored with the protective seam mining that the stress (strain) and deformation in the area of the protected coal seam, indicating that the effect of pressure relief and permeability improvement has the spatiotemporal difference. The maximum deformation of the protected coal seam is 80 mm, which is consistent with the theoretical result.