应力路径对煤岩渗透率影响实验研究

Experimental Study on the Influence of Stress Path on Permeability of Coal Rocks

依据煤岩体在巷道开挖后应力出现重分布特征,利用CGMS煤层瓦斯气液相对渗透率测试系统,对屯留煤矿煤样施加不同应力组合以研究三轴加载条件下渗透率与应力、温度之间的耦合关系。实验结果表明,渗透率随应力、温度的增加而减小,各个方向的应力对渗透率的影响程度不同,且差别较大;与应力相比,温度对渗透率的影响相对较小。得出了渗透率与三轴应力和温度之间的关系,并对温度和应力对渗透率的影响进行了理论分析。

According to the characteristic of in-situ stress redistribution of the coal surrounding rock caused by excavation,different stress on coal sample from Tunliu coal mine are jointed to investigate the coupled relation among permeability,stress and temperature under true tri-axial stress condition by using the test system of relative gas-liquid permeability of CGMS coal bed gas.The tests showed that the permeability of coal sample tends to decrease with the increase of stress and temperature,and Stress in different direction has different effect on permeability,which varies greatly.Temperature has less effect on the permeability significantly compared with the stress.Therefore,the relationship of permeability,stress and temperature is obtained and the effect of temperature and stress on permeability is theoretically analyzed.