NON-LINEAR BURGERS' SEA-ICE MODEL CONGSIDERING DAMAGE EFFECTS AND ITS NUMERICAL APPLICATION

Based on the published creep experiments of sea ice, a non-linear Burgers' sea-ice model, considering damage effects, is proposed. This model improves the sea-ice model presented by Jordaan through considering transition strain rate effects, which make it applicable in high strain rate conditions. The influence of strain rate and confining pressure on the damage process of sea ice is reflected by the experimental failure criteria proposed in this model. The iceberg model is implemented using an implicit integration mid-point (Crank-Nicolson) method and is incorporated into the code LS-DYNA by a user-defined material subroutine. Laboratory-scale experiments (creep experiments) and reality-scale experiment (iceberg-rigid steel plate collisions) are simulated. The curves of strain relations in time series, and area-pressure curves and contact force-penetration relations in time series in iceberg-rigid plate collisions are studied. The simulation results show that the proposed iceberg material model yields reasonably good results.