NRC has developed sophisticated numerical models that accurately predict ice loads and ice failure behaviour for both level ice and ice rubble. One such model uses an implicit particle-in-cell (iPIC) approach in which an assembly of discrete particles represents the ice cover. The program output includes grounding locations, force data, pressure, thickness and concentration contour data. The model has been used to examine ice interacting with rubblemound berms, narrow and wide bridge piers, ice pile-up scenarios, and ice flow with respect to safe evacuation from structures. A 3D version of the iPIC numerical model has been used to model ice-structure interaction scenarios in the Caspian and Beaufort seas.