A Method for Improvement of the Heating Efficiency of Conductive Asphalt Pavement

Conductive asphalt concrete (CAC) has been proposed as an alternative method for removal of snow and ice from pavements. Most previous literature focused mainly on the material composition, mixing, and preparation methodology, electrical and mechanical performance evaluation of CAC, while few studies were available about its electric heating behavior. After analyzing the heat transfer balance involved in the snow melting process, this paper then provided a method to improve the heating efficiency of CAC and hence accelerate the snow melting process. Small-scale slabs were designed for laboratory electric heating tests and three different materials (including slurry seal, expanded shale, and waterproofing material) were employed to prepare the thermal insulation layer paved between the conductive layer and the bottom layer. Slabs were electric-heated under different initial temperatures and applied power. The results show that waterproofing slab exhibited the best insulating effect, followed by expanded shale and slurry seal, respectively. Insulation layers with low thermal conductivity were effective in improving the performance of the snow melting system. Furthermore, the effect of the insulation layer on heating efficiency was more significant under greater applied power.