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

Ice and snow are usually classified as a viscoelastic or viscoplastic materials 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 rates, porous ice and snow exhibit brittle behavior, but experience high viscous and plastic flow at temperatures close to the melting point and low rates. At the macroscopic level, nonlinearity is not necessarily attributed to permanent changes in the material or yielding but mainly to micro cracks, intergranular sliding, porosity collapse and crack propagation. In this paper, this complex behavior is described with a full microstructure-based model. Classical rheological models and beam theory are used to describe aspects of creep and fracture of granular ice and snow.