载荷作用下煤体变形与渗透性的相关性研究

利用含瓦斯煤热流固耦合三轴伺服渗流装置，进行了不同气体压力作用下煤样全应力应变过程的瓦斯渗流实验。实验结果显示，煤样渗透率与变形之间存在内在关联，渗透率变化呈现阶段性特点。基于考虑气体吸附性的含瓦斯煤有效应力，建立了加载煤样变形与渗透率的相关性模型，研究受荷煤样变形与瓦斯渗流的相互关系。理论分析表明：当应力控制边界条件时，渗透率与煤样变形密切相关；煤样渗透率的变化受到有效应力、煤样变形模量、孔隙率和气体吸附性的共同作用；有效应力系数是联系煤样变形和渗透率的关键参量。由于理论计算结果与实验曲线较为接近，因此模型反映了不同瓦斯压力下加载煤样变形与渗透率变化的基本特征。

Pertinence study on deformation and permeability of coal containing methane during loading process

Considering that coal deformation and gas flow occur at the same time while mining,coal tri-axial laboratory experiments were conducted.Coal strain and permeability at different methane pressures were measured simultaneously during loading process.The tests indicate that there is relation between coal strain and permeability during loading process,and coal strain and permeability change by phases.Based on analysis of the effective stress for gassy coal,a pertinence model on coal deformation and permeability was proposed in this work.It is shown that the effective stress,coal deformation modulus,porosity and gas sorption affect coal deformation and permeability in the condition of stress controlled.It is worthwhile to note that the effective stress parameter is the key to establish communication between coal strain and permeability.The theoretical results match with the experimental curves,so this pertinence model can embody the fundamental characteristic of coal deformation and permeability at different methane pressures under loading.