瓦斯抽采钻孔孔周煤体的应力变化是影响其渗透特性的重要因素之一。为研究瓦斯抽采孔周不同破碎程度的煤体渗透特性，采用连续级配法制备不同粒径区间的煤颗粒组合试样，开展不同Talbol幂指数n的三轴渗透试验，分析有效应力对破碎煤样孔隙结构和渗透特性的影响。结果表明：在加载过程中，轴向应力通过改变破碎煤体孔隙率从而影响渗透率，其随轴向应力升高呈幂指数降低。加载初期，轴向应力升高使得煤样体积压缩，其内部空隙闭合，引起孔隙率减小及渗透作用减弱，导致渗透率降低。当轴向应力加载到孔隙率趋于0.1时，煤样内部密实使得渗透率趋于稳定；破碎煤体Talbol幂指数n从0.1到1.0增大的过程中，渗透率k呈现出缓慢、线性、指数3个增长阶段，分别受低级粒径、粒径比例、高级粒径的影响。渗流速度受Talbol幂指数、压力梯度、围压和轴向应力的共同影响，但压力梯度的作用更为显著，表现出Talbol幂指数和压力梯度越大，围压和轴向应力越小，渗流速度越大，存在渗流速度的Talbol幂指数促进效应和渗流速度的轴向应力及围压抑制效应；有效应力能较好地表征渗流速度的轴向应力及围压抑制效应，不同Talbol幂指数的破碎煤体渗透率随着有效应力的增大总体上呈指数衰减，但Talbol幂指数增大对渗透率的促进作用逐步减弱，而有效应力对渗透率的抑制作用和幅值效应逐渐强化。有效应力与渗透率的关系方程参数变化存在与渗透率曲线对应的3个阶段。随着Talbol幂指数n增大，关系方程参数a逐渐减小，有效应力的抑制作用增强；而b逐渐增大，幅值效应逐渐强化。

The stress change of coal body around the gas drainage borehole is one of the important factors affecting its permeability. In order to study the permeability with different degrees of fragmentation around the gas drainage boreholes, some coal particle composite samples with different range of particle diameter were prepared by the method of continuous grading, and the triaxial permeability tests with different Talbol power exponent n were carried out to analyze the influence of the effective stress on the internal structure and permeability characteristics of the fragmented coal samples. The results show that during the loading process, the axial pressure affects the permeability by changing the porosity of the broken coal, which decreases exponentially with the increase of the axial pressure. At the early stage of loading, the increase of axial pressure makes the volume of coal sample compressed, and the internal voids are closed, which causes the decrease of porosity and the weakening of permeability, resulting in the decrease of permeability. When the axial pressure is loaded with the porosity tends to 0.1, the internal compact structure of the coal sample makes a stable permeability. In the process of increasing the Talbol power exponent n of broken coal from 0.1 to 1.0, the permeability k shows three growth periods that are slow, linear and exponential stages, which are affected by the low-grade size particle, ratio of particle size and high-grade size particle respectively. The velocity of permeate is affected by the Talbol power exponent, pressure gradient, confining and axial pressure, however, the effect of pressure gradient is more significant. The larger the Talbol power exponent and pressure gradient with the smaller the confining pressure and axial pressure are, the larger the velocity of permeate is. There are the Talbol power exponent promotion effect of permeate velocity and the axial pressure and confining pressure inhibition effect of permeate velocity. The effective stress can characterize the inhibition effect of permeate velocity caused by the axial and confining pressure very well. The permeability of broken coal with different Talbol power exponents generally decays exponentially with the increase of effective stress, but the promotion effect of the Talbol power exponent on permeability gradually weakens, while the inhibition and amplitude effect of the effective stress on permeability gradually strengthen. The parameter change of the equation between the effective stress and permeability has three stages corresponding to the permeability curve. With the increase of the Talbol power exponent n, the parameter a of the equation decreases gradually, and the inhibition effect of the effective stress increases, while the increase of b, and the amplitude effect is gradually strengthened.