The flow properties of crushed ice under plane-strain conditions are examined. The analysis is based on a set laboratory experiments. The geometric configuration provided a wide range of pressures and material behaviors. At the early stages of the extrusion, and near the exit, where pressures are low, models based on Mohr-Coulomb flow theory describe the extrusion of crushed ice satisfactorily. At more advanced stages of the tests, high pressures developed, crushed ice became fused, and its behavior was similar to that of highly damaged polycrystalline ice. An extrusion model based on a nonlinear viscous flow is presented. This formulation is appropriate for the pressure ranges encountered in ice-structure interaction. After the initial compaction of the material, the dynamic force characteristics similar and cracking are not necessary to produce the dynamic effect in the ice-structure interaction. The vibrations appear to be related to variations in the width of the fused zone of ice.