为了研究在抽采负压作用下、三轴加卸载过程中原煤体试件瓦斯渗透率变化特征，在三轴渗流实验仪的基础上，开发出一种负压可控的流固耦合三轴伺服渗流实验装置，实验结果表明：在相同围压、轴压及进气口瓦斯压力条件下，随着加载负压的增大，煤体瓦斯渗透率随之增大，然而最终趋于一定值；在围压、抽采负压及进气口瓦斯压力保持恒定条件下瓦斯渗透率随着加载轴压的增大而增大，达到峰值后则随着轴压的增大而减小；轴压卸载到零过程中瓦斯渗透率逐渐增大，然而难以恢复到初始渗透率，可能与煤体的塑性变形有关；高应力作用下，提高进出气口压差对提高瓦斯渗透率影响甚微。%In order to study the variation characteristics of gas permeability of raw coal sample in triaxial loading-unloading process under negative pressure, based on triaxial seepage experiment instrument, a fluid-solid coupled triaxial stress seepage experimental device is developed. The experiment results show that: under the same confining pressure, axial pressure and gas inlet pressure conditions, with the increase of loading negative pressure, the gas permeability of raw coal increases, however, it tends to a certain value; with constant confining pressure, pumping negative pressure and gas inlet pressure, the gas permeability increases with the increase of axial compression, after reaching the peak value, it declines with the increase of axial pressure; during the unloading process of axial pressure to zero, gas permeability increases gradually, however, it can hardly be restored to the initial, which could be related to the plastic deformation of coal;under high stress, improving the differential pressure of air inlet and outlet has little effect on gas permeability enhancement.
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