为了研究围压和饱和度对含瓦斯水合物煤体宏细观力学特性的影响规律，对它进行三轴压缩试验离散元模拟。首先，利用颗粒流程序PFC3D构建3种不同饱和度的含瓦斯水合物煤试样数值模型，其中水合物的胶结作用通过平行黏结模型进行模拟。其次，通过与室内三轴试验结果进行比较，标定能够反映其力学特性的细观参数。试验结果和模拟结果的应力−应变曲线趋势基本吻合，破坏强度、强度参数误差率均在10%以内，从而验证所建模型的可靠性。进而，对不同围压下含瓦斯水合物煤体三轴试验进行离散元模拟，从应力−应变曲线以及速度场、接触力链、配位数及孔隙率角度分别分析其宏细观力学特征。结果表明：离散元模拟结果与室内试验结果吻合较好，整体上能够较好模拟试样的应变硬化特征。从速度场变化规律可以发现，低饱和度下试样剪胀程度较高，高围压下试样剪缩程度较高。不同饱和度、围压条件下，破坏强度处的主力链传递方向没有明显区别。随着围压和饱和度的增大，接触力增大，接触力链个数增加；配位数整体呈增大趋势，孔隙率整体呈减小趋势，使得试样强度增强；摩擦是维持试样细观力学体系稳定的重要因素。研究结果从细观尺度上揭示饱和度和围压对含瓦斯水合物煤体强度变形破坏等宏观力学特性的影响机制，为含瓦斯水合物煤体三轴试验离散元模拟建模提供理论参考以及为利用水合物技术预防煤与瓦斯突出提供依据。

Discrete element simulation of triaxial compression test was carried out to study the effects of confining pressure and saturation on the macro and meso mechanical properties of gas hydrate bearing coal (GHBC). Firstly, the numerical models of three kinds of GHBC with different saturations were established by particle flow program PFC3D, with the cementation of hydrate simulated by parallel bonding model. Then, the meso mechanical parameters were calibrated by using the results of the physical triaxial test. The stress-strain curves of the physical tests agree with the simulated results, with the failure strength and strength parameter error rate within 10%, which verifies the reliability of the established numerical model. Furthermore, the triaxial tests of GHBC were performed under different confining pressures to analyze the macro and meso-mechanical characteristics such as the stress-strain curve, velocity field, contact force chain, coordination number and porosity. The results show that the discrete element simulation results agree well with the indoor test results, especially simulating the strain hardening characteristics of the sample. The velocity field reveals a higher dilatancy degree under low saturation and a higher contraction degree under the high confining pressure of the samples. There is no obvious difference in the main chain transfer direction at the failure strength under different saturations and confining pressures. The contact force, the number of contact force chains, as well as the coordination number increase with the increase of confining pressure and saturation, while the porosity tends to decrease, which enhances the strength of the samples. The friction is an important factor to maintain the stability of the meso mechanical system of the samples. The influence mechanism of saturation and confining pressure on the strength deformation and failure of GHBC is revealed from the microscale, which provides a theoretical reference for the discrete element simulation of GHBC triaxial test and for the prevention of coal and gas outburst by hydrate technology.