在现有有效应力计算公式基础上,考虑多孔介质在三轴压缩状态下产生损伤的影响,修正了有效应力计算公式,并通过试验验证了该公式可以较好的描述含瓦斯煤在三轴压缩下的全应力-应变过程。三轴压缩下渗流试验表明:含瓦斯煤样在峰值点前的有效体积应力和渗透率为负指数关系;在峰值点后,有效体积应力和渗透率仍然存在指数关系,但系数发生了变化,和峰值点前不同。含瓦斯煤样的渗透率同有效体积应力呈反方向变化,即在有效体积应力增大时,渗透率减小,反之亦然。
Considering the damage effect of porous media under triaxial compression,the calculation formula of effective stress is modified.It is verified that the formula can very well describe complete stress-strain process of gas-filled coal under triaxial compression.The permeability experiments under triaxial compression show that the relationship between the effective volumetric stress and permeability of gas-filled coal samples is negative exponent before the peak stress.It is still exponentially after the peak point,but the coefficient changes.The permeability of the gas-filled coal samples changes in reverse direction with the effective volumetric stress,that is,the effective volumetric stress increases when the permeability decreases,and vice versa.