Model of structure and mechanical properties of dry granular snow

The paper discusses the verification of a previously developed structural dry-snow model based on the regular packing of isometric grains connected by rigid bonds. Using this model, we consider the probable snow-compaction mechanisms at different snow-density ranges (from new to dense snow), limited by critical densities corresponding to the real values of the structural indices of the model: texture looseness, bond rigidity and coordination number. We also obtain the analytic expression for longitudinal wave velocity and for bulk compressibility of snow as functions of density and structural indices. The calculation enables us for the first time to show the whole range of possible values of these important characteristics and to deduce the most probable configuration of the ice matrix in snow of various densities corresponding to the experimental data available an the snow-texture peculiarities and elastic-wave velocities. The model can be used to comprehend the changes in snow mechanical properties during compaction, as well as the steps by which it proceeds.