为了揭示应力、气体吸附共同作用下煤岩的结构变化规律，对不同轴向载荷、不同瓦斯压力条件下的煤样进行CT扫描，基于CT图像定义了体素孔隙率α，分析了煤样体积应变、CT图像灰度及孔隙分布的变化规律。结果表明：体素孔隙率α可以反映应力、气体吸附共同作用下煤样内部不同尺度孔隙结构的变化；0<α≤20％时体素区域在瓦斯作用中起主导作用，α>40％时体素区域主要起着瓦斯运移通道作用；瓦斯吸附首先发生在0<α≤10％的体素区域，随着轴压的增大，吸附逐渐对10％<α≤20％的体素区域产生作用；应力比气体吸附对煤样孔隙结构的改变作用更为显著。%In order to reveal the coal and rock structure variation law under the joint role of the stress and gas adsorption,a CT scanning was conducted on the coal samples under the conditions of the different axial loading and different gas pressures.Based on the CT images, the voxel porosityαwas defined and the volume strain of the coal samples,CT image grey scale and pore distribution variation law were analyzed.the results showed that the voxel porosityαcould reflect the different size pore structure variation within the coal samples under the joint role of the stress and gas adsorption.When 0<α≤20%,the voxel region in the gas role would play a leading role.Whenα>40%,the voxel region would mainly play a role of gas migration channel.Gas adsorption would firstly occur in the 0<α≤10% voxel region and with the axial pressure increased,the adsorption would steadily play a role to the 10%<α≤20% voxel region.Compared to the gas adsorption, the stress would have a change role to the pore structure of the coal samples remarkably.
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