Mastering the damage evolution and gas–solid coupling behaviours of coal containing gas allows for the in depth recognition of underlying coal and gas outburst mechanisms. In the current study, we derive an expression for the damage factor of coal containing gas based on the theory of energy conservation to monitor the evolution law of the damage factor during the entire stress–strain process. Under conventional triaxial compression and three mining stress paths, the critical damage factors of the loaded coal containing gas are less than 0.35, and the damage factors of residual strength are greater than 0.6. The critical damage factor of coal containing gas under mining stress paths is larger than that of conventional triaxial compression. Furthermore, based on related rock and damage mechanics theories, we establish a constitutive equation for loaded coal containing gas that considers damage evolution. A permeability model accounting for the damage evolution of loaded coal containing gas is derived, allowing us to construct a gas–solid coupling model that takes the damage evolution of loaded coal containing gas into account. The results have a practical significance for the damage evolution and instability failure law of loaded coal containing gas under gas–solid coupling.

掌握含煤瓦斯的破坏演化和气固耦合行为，可以深入识别潜在的煤与瓦斯突出机理。在当前的研究中，我们基于能量守恒理论来推导含煤瓦斯的破坏因子的表达式，以监测整个应力-应变过程中破坏因子的演变规律。在常规的三轴压缩和三个开采应力路径下，含煤瓦斯的临界破坏因子小于0.35，剩余强度的破坏因子大于0.6。含煤气体在开采应力路径下的临界破坏因子大于常规三轴压缩的破坏因子。此外，根据相关的岩石和破坏力学理论，我们建立了包含气体的煤的本构方程，该方程考虑了损伤的发展。推导了一个计算含煤气体破坏演化的渗透率模型，使我们能够构建一个气固耦合模型，该模型考虑了含煤气体破坏演化的影响。该结果对气固耦合下含煤瓦斯的破坏演化和失稳破坏规律具有实际意义。