Industrial Economic Bureau of Bozhou District, Zunyi City

急倾斜煤层群开采存在复杂的岩层运移过程并易导致强矿压事故的发生。为保障兴安煤矿煤层群的安全开采,采用保护层开采技术对主采煤层进行卸压优化,依托FLAC3D数值模拟软件建立急倾斜煤层开采数值模型,探究保护层开采条件下的采场应力、位移与被保护煤层应力、位移的分布演化规律,利用理论计算方法分析了有效卸压保护范围,验证保护层开采技术的可靠性。研究结果表明:急倾斜煤层保护层开采条件下会出现位移与应力扩展的不共轴现象;保护层推进过程中,采场应力与位移演化呈现出初始增长、快速增长、逐渐稳定的3阶段演化规律;保护层开采的有效卸压范围超过80%。

The mining of steeply inclined coal seam group involves complex rock stratum migration processes and can easily lead to strong mine pressure accidents. In order to ensure the safe mining of the coal seam group in Xing'an Coal Mine, protective layer mining technology is used to optimize the pressure relief of the main mined coal seam. A numerical model of steeply inclined coal seam mining is established using FLAC numerical simulation software to explore the distribution and evolution law of stress and displacement in the stope and the protected coal seam stress and displacement under the mining condition of the protective layer. Theoretical calculation methods are used to analyze the effective pressure relief protection range and verify the reliability of protective layer mining technology. The research results indicate that under the mining condition of steeply inclined coal seam protective layer, there will be a non coaxial phenomenon of displacement and stress expansion. During the advancement process of the protective layer, the evolution of stope stress and displacement shows a three-stage evolution law of initial growth, rapid growth, and gradual stability. The effective pressure relief range of the protective layer mining exceeds 80%.