含瓦斯煤卸围压蠕变试验及其理论模型研究

以重庆松藻煤电公司打通一矿突出煤层取得的煤样为研究对象，运用自制的含瓦斯煤三轴蠕变加载渗流试验系统，进行了含瓦斯煤卸围压蠕变与渗流试验研究，分析了其黏塑性本构关系与考虑Klinkenberg效应的卸压瓦斯渗流规律。结果表明：通过卸围压可使含瓦斯煤加速破坏，对于脆性煤岩体则容易引起冲击地压或煤与瓦斯突出。由于煤样在加压再卸压的过程中产生大量的宏观裂隙，优化了煤体中孔隙的连通性，会引起瓦斯流动速度显著增加。改进了Chaboche黏塑性本构模型，可用以描述含瓦斯煤的卸压短期蠕变破坏。通过实验数据可以获得该本构模型中的系列参数，并使之与含瓦斯煤的卸压变形吻合。通过试验得出了考虑Klinkenberg效应的卸围压过程中瓦斯流量的变化规律、视渗透率与滑脱系数。

Creep experimental and theory model on coal containing gas under the condition of unloading confining pressure

Using self developed triaxial creep and seepage experimental installation，the creep experiment of coal containing gas under unloading condition were studied.The coal specimen was taken from gas outburst coal seam 7 of Datong No.1 Coal Mine which belong to Songzao C &; E Co.，Ltd.According to the experiment result，the viscoplasticity constitutive relation and gas flowing，considering the Klinkenberg effect，were discussed too.The results show that unloading can accelerate the failure，so it can lead to rock burst and gas outburst.The macrofissure induced by unloading can increase the gas flow velocity significantly.The modified Chaboche viscoplasiticity constitutive relation can describe the short term creep failure of coal containing gas.A series of parameters can be educed from the experimental data.The change law of gas flux，apparent permeability and spondylolisthesis coefficient were achieved from the study about unloading creep and seepage test.