冲击地压与瓦斯等灾害制约了我国煤矿安全高效开采，但诸多煤岩动力灾害的发生机理不明。从巷道围岩冲击−瓦斯灾害实例出发，着重研究煤岩损伤破裂演化规律与模型。开展了X射线高精度显微CT扫描试验，利用三维重构技术获得了冲击倾向性煤高分辨率三维数字岩心图像，定量分析了非连续结构分布特征；采用计盒维数法和三维可视化软件AVIZO编程计算，得到了矿物条带和裂隙结构的表征参数；基于CT扫描重构和统计强度理论，提出了一种考虑三参量韦伯分布、瓦斯作用与有效应力的煤岩损伤破裂模型；进而，开展了含瓦斯煤岩三轴压缩试验，求解模型参数并验证模型可靠，揭示了煤岩渐进破坏过程中的损伤演化规律。具体而言，显微CT扫描重构和分形计算结果表明，冲击倾向煤内部矿物条带的表面积和分形维数分别处于0.0035～0.0137和1.1214～1.2342之间，而裂隙结构的表面积占比和分形维数则分别处于0.0006～0.0040和1.0651～1.1454范围。矿物条带的表面积占比和分形维数整体上大于裂隙结构的，说明冲击倾向煤内部的非连续结构数量多且分布复杂。此外，含瓦斯煤岩三轴压缩试验结果表明，围压作用下煤样应力应变关系呈现出典型的I类曲线特征，以剪切破坏为主，峰值强度和峰值应变随围压升高而增大。进一步，给出了损伤破裂模型7个参数的确定方法，并利用试验结果求解了模型参数和损伤变量。计算结果表明，该模型能较准确地反映煤岩压缩变形、准线弹性变形、塑性变形、峰值强度和峰后软化等渐进破坏特征。而且，在前2个阶段煤岩损伤变量小于0.2，进入塑性阶段尤其是峰后阶段，损伤变量急剧增大直至破裂。因此，提出了损伤阈值的概念，建议将损伤阈值0.2作为煤岩损伤破裂的预警值。研究结果将为煤岩动力灾害的发生机理、预警及防控提供理论支撑。

Coal rock dynamic disasters such as rockburst and gas outbursts pose severe threats to the safe and efficient mining of coal mines in China; however, the mechanical mechanisms of those disasters are still unknown. Therefore, the evolution law and constitutive model of damage and fracture of coal rock was emphatically studied, starting from the rockburst-gas disaster that occurred at the coal mine roadway. Firstly, the X-ray high-precision micro-CT scanning experiment was performed, and the high-resolution 3D digital core of burst-prone coal was built utilizing 3D reconstruction technology. Furthermore, the box-counting dimension method and the 3D visual image processing software AVIZO were used to calculate the characteristic parameters of mineral bands and crack structures inside the coal sample. Secondly, a damage-fracture constitutive model considering three-parameter Weibull distribution, gas influence, and effective stress was proposed, based on CT scanning reconstruction and statistical strength theory. Thirdly, the triaxial compression experiments of gas-bearing coal were conducted, the model parameters were calculated using experimental results, the model was verified, and the damage evolution law of the progressive failure process of coal rock was revealed. Specifically, the experimental results of micro-CT scanning reconstruction and fractal calculation show that the surface area ratio and fractal dimension of the mineral bands are 0.0035−0.0137 and 1.1214−1.2342 respectively, while that of the fracture structures are 0.0006−0.0040 and 1.0651−1.1454 respectively. The surface area ratio and fractal dimension of mineral bands are generally larger than those of fracture structures, indicating that the number of discontinuous structures of burst-prone coal is significant, and its distribution is complex. Furthermore, the experimental results show that stress-strain curves are characterized by the class I curve; shear fracture usually occurs under triaxial compressive loads. The peak strength and peak strain increase with the rise in confining pressure. Moreover, the determination method of seven parameters within the damage fracture model is given, and those parameters and damage variable are solved based on experimental results. The calculation results show that this model can accurately reflect the progressive failure characteristics of coal rock, such as compressive deformation, quasi-linear elastic deformation, plastic deformation, peak strength, and post-peak softening. Additionally, in the first two stages, the damage variable of coal rock is less than 0.2. When it enters the plastic stage, especially in the post-peak step, the damage variable increases sharply until the failure occurs. Hence, the concept of damage threshold is proposed; here, the damage threshold of 0.2 is recommended as the early warning value of damage fracture of coal rock. The findings will further promote the development of damage mechanics and provide a theoretical basis for the prevention and control of coal and rock dynamic disasters.