沿空掘巷条件下小区段煤柱受多重采动影响，受采动影响的煤岩体渗透率会因为采动裂隙、原生裂隙的发育与压实而发生改变，确定不同采动阶段小区段煤柱渗透率演化规律是同层位邻近采空区气−水灾害防控的理论基础。以大同矿区石炭系特厚煤层沿空掘巷小区段煤柱开采为工程背景，通过地应力测试、数值模拟的方法，综合确定不同采动阶段小区段煤层所处应力场的分布特征，为试验研究应力路径的确定提供依据，应用DJG-Ⅱ型三轴加载煤岩渗流测试装备进行不同采动阶段煤柱渗透率演化试验研究。研究结果表明：建立了沿空掘巷小区段煤柱不同采动阶段渗透率与应力的定量影响关系，总体表现为渗透率随着轴向应力的增大而减小，卸载阶段渗透率随着轴压的减小而增大；揭示不同采动阶段小区段煤柱应力−应变−渗透率的演化规律，在第一、第二阶段加卸载时，煤样变形还处于弹性变形阶段，渗透率变化幅度与速率都较为平缓。在第三次采动影响阶段，试件出现不可逆的塑性破坏使得渗透率急剧增加，增幅速率也明显大于前2个采动阶段，小煤柱渗透率较初始渗透率增大最多为324.389倍，该阶段小煤柱发生破坏失去了气−水阻隔性能，明确了特厚煤层沿空掘巷工程中前2个采动阶段宽6 m小煤柱没有破坏的特征。研究成果可为坚硬顶板特厚煤层沿空掘巷开采条件下，小区段煤柱在不同采动阶段渗透率演化特征研究、邻近采空区气−水灾害防控等提供参考或理论支撑。

Under the condition of roadway driving along goaf, slender coal pillar is affected by multiple mining-induced disturbances, and the permeability of coal and rock mass affected by mining will change due to the development and compaction of mining fractures and primary fractures. Determining the evolution of slender coal pillar permeability at different mining stages is the theoretical basis for the prevention and control of gas water disasters in adjacent goaf at the same layer. Taking the mining with slender coal gate pillar of the Carboniferous extra thick coal seam in Datong Mining Area as the engineering background, the distribution characteristics of the stress field for the slender coal gate pillar of the coal seam in different mining stages are comprehensively determined by the methods of geostress testing and numerical simulation, which provides a basis for the determination of the stress path for experimental research. The DJG - Ⅱ triaxial loading coal rock seepage testing equipment was used to conduct experimental research on the evolution of coal pillar permeability in different mining stages. The research results are as follows: The quantitative influence relationship between permeability and stress of slender coal gate pillar in different mining stages is established. The overall performance is that the permeability decreases with the increase of axial stress, and the permeability increases with the decrease of axial pressure in unloading stage; It reveals the evolution of stress strain permeability of the coal pillar in different mining stages. When loading and unloading in the first and second stages, the deformation of coal sample is still in the elastic deformation stage, and the change amplitude and rate of permeability are relatively gentle. In the third mining-impacted stage, the irreversible plastic failure of the specimen made the permeability increase sharply, and the rate of increase was also significantly greater than the first two mining stages. The permeability of slender coal pillar increased by 324.389 times compared with the initial permeability. In this stage, the slender coal pillar was damaged and lost its gas water barrier performance. It was clear that the 6 m small coal pillar was not damaged in the first two mining stages of the super thick coal seam gob side entry project. The research results can provide reference or theoretical support for the study of permeability evolution characteristics of slender coal pillar in different mining stages, and the prevention and control of gas water disasters in adjacent goaf under the condition of gob side entry mining in hard roof extra thick coal seams.