Study of overburden of shallow coal seam , especially the relationship between permeability and stress variation of weathered rocks in mining conditions , has important significance for revealing roof water inrush mechanism about coal mining under the loose aquifer .The samples collected from shallow coal seam in West Ventilation Shaft of Panji No .3 Coal Mine were used for permeability tests of full stress -strain under triaxial compression.The tests revealed the permeability change rule of weathered rock and fresh rock in the process of rock deformation and failure .And according to the tests , the seepage-stress coupling equation was fitted .The results showed that the permeability of rocks is the largest in the strain softening stage after peak value occurrence no matter whether weathered or not .The relationship between stress and permeability obeys the negative expo-nential function before peak value occurrence , while it obeys positive exponential function after peak value occur-rence.After the yield, the permeability growth multiple of weathered rock or weak rock is far less than that of hard rock .This indicates that the permeability of the soft and weak roof overburden has little change even if the rock is affected by the mining failure .It is advantageous to reduce waterproof pillar in coal mining under the loosen aquifer .%研究浅埋煤层覆岩,尤其是风化岩石在采动条件下的渗透性与应力变化的关系,对揭示松散含水层下开采顶板突水机理具有重要意义. 运用采自潘三煤矿西风井浅部煤层覆岩样进行三轴全应力-应变渗透试验,分析了风化和未风化岩石在变形破坏中的渗透率变化规律,并拟合出渗流-应力耦合方程. 研究结果表明:无论风化与否,岩石一般皆在峰值后的应变软化阶段渗透性能才达到最大,峰值前的应力-渗透率的关系呈负指数函数关系,而峰值后二者呈现正指数关系;风化岩石或软弱岩石在屈服后,渗透率的增长倍数远远不如硬质岩石,表明顶板软弱覆岩即使受采动破坏的影响,其渗透率也变化不大,这对松散含水层下采煤缩小防水煤柱开采是有利的.
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