During snowfall loose snow sticks to the underlying pavement, forming a hard crust that can be difficult to remove. In order to ensure good road traffic safety, winter maintenance personnel use several operations, such as mechanical removal and chemical altering, to keep snow plowable. One chemical, commonly applied on roads, is sodium chloride (salt). Recent studies establish that very small amounts of salt are sufficient to weaken compacted snow substantially, meaning that the mechanical properties of salted snow are different from dry snow. This change in the mechanical properties of salted snow, however, has not been considered when studying tire–pavement interaction in snowy conditions.
In an attempt to better understand salt snow as a material, this paper presents an experimental investigation of salted snow under uniaxial compression. The study examines the density and the loss of mass of snow after compression for different solution contents and compression speeds.
Samples of snow were mixed with sodium chloride solution at different liquid contents. The snow samples were then compressed by an MTS uniaxial compression machine, up to an applied load of approximately 2 bars, roughly corresponding to the pressure applied by a car. Applied forces and dry density were measured for each test after compression. Based on the results carried out in this study, we found that: Salted snow gets a higher density after compaction compared to dry snow, also flows easier than dry snow, giving a larger loss of mass during uniaxial compression. The dry density after compaction increases with compaction speed for dry snow but decreases with compaction speed for salted snow.
The effect of the solution on the compressibility and flowability of the material and its relevance for tire–pavement interaction are discussed.