采空区及煤柱下回采巷道围岩控制技术
Surrounding Rock Control Technology of Roadway Under Goaf and Coal Pillars
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摘要: 为有效控制采空区及煤柱下方的回采巷道失稳破坏,采用现场监测和数值模拟的方法,对采空区底板岩层应力分布规律及巷道失稳破坏原因进行分析,同时根据分区支护的思想对不同区域巷道断面支护参数进行优化。研究表明:煤柱在底板岩层中传递的垂直集中应力是下部煤层回采巷道发生失稳破坏的主导因素。受遗留煤柱传递荷载影响,下部9#煤层应力呈现单峰值的“钟形”分布,根据其应力分布规律,对交叉区域巷道进行分区优化支护,提出不同区域的支护方案。工程实践表明,支护参数优化后,巷道得到了有效地控制。Abstract: To effectively control the instability failure of mining roadway under goaf and coal pillar, the stress distribution law of floor strata in goaf and the causes of instability failure of roadway are analyzed by means of field monitoring and numerical simulation. And the support parameters of roadway cross section in different areas are optimized according to the idea of zoning support. The study shows that the vertical concentrated stress transmitted by coal pillars in floor strata is the dominant factor for instability failure of mining roadway in lower coal seam. Influenced by the transfer load of the remaining pillars, the stress of No. 9 coal seam in the lower part presents a single peak “bell” distribution. According to the stress distribution law, the roadways in the intersection area are subdivided and optimized, and the support schemes in different areas are proposed. Engineering practice shows that the roadway has been effectively controlled after the support parameters are optimized.