The seepage laws of coal and shale were studied by means of the conventional triaxial seepage simulation test.The experimental results showed that the permeability of shale sample is three orders of magnitude lower than that of coal sample.In order to compare the two,we introduce the permeability change ratio I,so that the difference between the two can be shown in the same picture.Based on these results,we suggested that the permeability of coal and shale has the same trend,the permeability variation of the two samples matches with the deformation characteristics of the rock and there is a minimum permeability point between the elastic phase and the plastic expansion phase,the permeability decreases with the increasing of confining pressure,but the attenuation amplitude and decay rate of coal are both higher than that of shale,and it also increases exponentially with the increase of the pore pressure,on the contrary,shale is more sensitive to gas pressure.%利用常规三轴渗流模拟实验装置,对煤和页岩的渗流规律进行了研究.实验表明:页岩样的渗透率要比煤样低3个数量级上,为了将两者进行对比,引入渗透率变化比I,这样就可以在同一幅图中显示两者的差异.研究进一步指出:煤、页岩的渗透率变化规律具有相同趋势;两者的渗透率变化与岩石的变形特性匹配,在弹性阶段和塑性扩展阶段之间存在渗透率极小值点;两者的渗透率随围压的增加呈负指数关系递减,煤的衰减幅度和衰减速率均大于页岩;随孔隙压力的增加呈指数形式增大,但页岩对气体压力更敏感.
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