含瓦斯煤样横向变形与瓦斯流动特性耦合关系试验研究

以二次成型煤样为研究对象，运用自行研制开发的含瓦斯煤热-流-固耦合三轴伺服渗流试验装置对含瓦斯煤样三轴加载过程中横向变形和与瓦斯流动特性的耦合关系进行了试验研究。结果表明：弹性力学定义的泊松比不能准确表征含瓦斯煤样的横纵应变特性，其关系可用二次函数表征；在预加载荷引起的横压向应变恢复阶段瓦斯流动速度变化呈先急剧降低再缓慢增加特性；在横向应变逐渐向扩张应化转变阶段，煤样内部的瓦斯流动速度呈单调缓慢增加趋势，且存在一个内部结构临界状态点使煤样内瓦斯流动速度最小；含瓦斯煤样处于横向压应变状态起始时的瓦斯流动速度要大于处于横向应变呈扩张状态末端时的瓦斯流动速度。

Experimental study of coupling relationship between lateral strain of coal containing gas and characteristics of gas flow

Taking second shaped coal samples as research object, the coupling relationship between characteristics of gas flow and lateral strain of coal containing gas under triaxial loading is studied by self-developed triaxial servo-controlled seepage equipment for thermo- fluid-solid coupling of coal containing gas. The results show: Poisson ratio defined by elastic mechanics can not accurately express the characteristics of axial strain and lateral strain of coal containing gas; the relationship can be properly expressed by quadratic function. Characteristics of gas flow velocity is showed by the law that firstly rapid decreased then slowly increased in restoration stage of lateral strain caused by preloading. Gas flow velocity can be showed by the law of monotonic slowly increased in transformable stage from lateral compressive strain to dilated strain; and there is a special internal structure critical state point where the gas flow velocity is the smallest. The gas flow velocity of coal containing gas at initial state of lateral compressive strain is larger than it at end state of lateral dilated strain.