Numerical Analysis of Ice Rubble with a Freeze-Bond Model in Dilated Polyhedral Discrete Element Method

Freezing in ice rubble is a common phenomenon in cold regions, which can consolidate loose blocks and change their mechanical properties. To model the cohesive effect in frozen ice rubble, and to describe the fragmentation behavior with a large external forces exerted, a freeze-bond model based on the dilated polyhedral discrete element method (DEM) is proposed. Herein, imaginary bonding is initialized at the contact points to transmit forces and moments, and the initiation of the damage is detected using the hybrid fracture model. The model is validated through the qualitative agreement between the simulation results and the analytical solution of two bonding particles. To study the effect of freeze-bond on the floating ice rubble, punch-through tests were simulated on the ice rubble under freezing and nonfreezing conditions. The deformation and resistance of the ice rubble are investigated during indenter penetration. The influence of the internal friction coefficient on the strength of the ice rubble is determined. The results indicate that the proposed model can properly describe the consolidated ice rubble, and the freeze-bond effect is of great significance to the ice rubble properties.