The high-speed and long-distance sliding characteristics of large-scale rock-ice avalanches usually make them a catastrophic event, which seriously threatens the safety of human beings and infrastructure. Obviously, apart from the lubrication of ice and water, the fragmentation of particles in the slip zone is also an important contribution to the hypermobility of rock-ice avalanches. Up to now, existing researches have not taken into account the impact of particle breakage on rock-ice landslides. In this paper, a thermal-hydro-mechanical (THM) model for the high-speed rock-ice avalanches is developed, which mainly considers the particle breakage due to sliding shear deformation and the ice melting caused by frictional heat. The results of the model analysis applied to the Chamoli avalanche indicate that particle fragmentation has a significant effect on landslide sliding. When the particle breakage is considered, the simulated velocity and displacement of landslide are closer to the existing research results. Both thermal pressurization and particle crushing are two important mechanisms that lead to a high-speed sliding of rock-ice landslide, and these two mechanisms affect each other. It is demonstrated from a set of sensitivity analyses that the initial grain size distribution, fractal dimension and the thickness of the slide mass have clear impacts on the evolution of the granular crushing index, which thus affects the characteristics of the landslide eventually. In particular, the sensitivity analysis of the slide thickness once again demonstrates the importance of considering particle fragmentation in the analysis of landslide sliding.

大规模岩冰雪崩的高速、长距离滑动特性通常使其成为灾难性事件，严重威胁人类和基础设施的安全。显然，除了冰和水的润滑作用外，滑移带中颗粒的破碎也是岩冰雪崩超活动性的重要贡献。目前，现有研究尚未考虑颗粒破碎对岩冰滑坡的影响。本文建立了高速岩冰雪崩的热流体力学（THM）模型，该模型主要考虑滑动剪切变形引起的颗粒破碎和摩擦热引起的冰融化。应用于Chamoli雪崩的模型分析结果表明，颗粒破碎对滑坡滑动具有显着影响。当考虑颗粒破碎时，模拟的滑坡速度和位移更接近现有的研究结果。热加压和颗粒破碎是导致岩冰滑坡高速滑动的两种重要机制，并且这两种机制相互影响。一组敏感性分析表明，初始粒度分布、分形维数和滑体厚度对粒体破碎指数的演化有明显影响，从而最终影响滑坡特征。特别是滑坡厚度的敏感性分析再次证明了在滑坡滑动分析中考虑颗粒破碎的重要性。