Development of a coupled DDA–SPH method and its application to fracture and dynamic simulation of ice-rock interaction

Rock-ice avalanches in high mountainous areas often pose serious threats to people's lives and infrastructure due to their high speed and long distance of movement. In this study, we examine the fracture process and interaction processes between rock and ice using the Discontinuous Deformation Analysis (DDA) coupled with smoothed particle hydrodynamics (SPH). We apply Glen's flow constitutive law to simulate the rheology of ice and enhance it by integrating the shear stress criterion to model the glacier fracture process. The effectiveness of the improved method was validated by comparing its stress–strain response and fracture morphology with experimental results from uniaxial compression ice tests. We then applied the improved method to simulate the Chamoli rock-ice avalanche, successfully reproducing the glacial fracture process and its impact on the fracture expansion of the underlying rock mass under temperature influence. This was then compared with historical remote sensing images, existing survey data, and station monitoring of ground motions. The evolution of shear stress and the transformation of the interaction mechanism during rock-ice movement were analyzed. Finally, we explored the impact of temperature on glacier creep and its potential to trigger rock-ice avalanches. Our findings highlight that temperature significantly influences glacier creep, which in turn affects glacier dynamics and the initiation of rock-ice avalanches in plateau mountainous regions.