Evaluating the thermal regime and unfrozen water content of snow accumulated in road ditches: A case study from northern Sweden

Accumulated snow in road ditches significantly influences the thermal regime of road embankmentsduring the winter season.Understanding the insulating effect of this snow cover is essentialto accurately assess the thermal behavior of the road structure. A field experiment was conductedin Luleå, northern Sweden, to evaluate the insulating properties of the snow accumulated ina ditch. This study mathematically investigates the thermal conductivity, a key parameter forassessing snow insulation, and the unfrozen water content over a 49-day period, based on insitu temperature and density measurements from the experimental site. The mechanical andthermal properties of snow layers accumulated in road ditches are expected to differ fromthose of undisturbed, naturally accumulated snow due to additional factors such as variationsin deposition history and the influence of nearby traffic. The results show that the snow in theditch, extending from the soil–snow interface to approximately 30