Some issues of changing snow density under compressive load

About 80% of the territory of the Russian Federation is covered with snow for a long period of time (5...10 months), which significantly affects the economy and lifestyle of the population. Snow, as a road building material, is a set of phases of a substance of the same nature, but in different aggregate states. Snow as a track bed is a complex spatial system, which in topological terms is defined as a poly-relief, polyzonal, poly-layered, and polydisperse medium. The materials forming the motion surfaces are evaluated according to independent parameters. Independent parameters are understood as such physical and mechanical properties of the material that do not depend on the method of their determination. So for snow these are: density, hardness, stiffness coefficient, cohesion, frictional properties, adhesion and freezing, moisture, temperature, structure and texture of the snow. To increase the hardness (bearing capacity) of the snow cover it is necessary to compact it as much as possible. Selection of specific pressures applied by machines should be based on a relationship between the value of the specific pressure and the density of the snow cover. Practical observations have shown that the ability of snow to compact depends on its temperature. Therefore, the authors conducted experimental studies to determine the relationship between specific pressures, applied to the snow cover, and its density. The studies were performed in the field conditions on virgin snow and in the laboratory of the departments LT4-MF and LT7-MF MGTU named after N.E. Bauman.