Micromechanical model for sintering and damage in viscoelastic porous ice and snow. Part I: Theory

Ice and snow have sometime been classified as a viscoelastic or viscoplastic mate- rial according to temperature, strain rate, pressure and time scale. Throughout experimental studies presented in the literature, it has been observed that at very low temperatures or high strain rate, porous ice and snow exhibit brittle behavior, but experience high viscous and plastic flow at temperatures closed to the melting point and low rates. At the macroscopic level nonlinearity is not necessarily attributed to material level permanent changes or yielding but mainly to micro cracks, porosity collapse and crack propagation. This paper attempts to address this complex behavior with a full microstructure based model.