Investigation of electrical heating in asphalt mixtures for pavement snow/ice melting

Asphalt pavements are the most prevalent pavement type throughout the world, but the accumulated snow and ice on pavements in winter pose serious threats to traffic safety. Constructing electrically heated asphalt pavements is an emerging technology for snow/ice removal. In this study, the electrical heating in asphalt mixtures through several potential approaches was investigated by laboratory experiments.

Firstly, the electrically conductive hot mix asphalt mixtures utilizing the most widely used conductive materials including carbon fibers and/or graphite were developed for pavement snow/ice-melting. The results indicated that a volume resistivity of 0.7 ~2.7 Ω·m could be used as the design electrical resistivity and it was feasible to make electrically conductive hot mix asphalt mixtures utilizing carbon fibers and/or graphite powders to achieve the design electrical resistivity without compromising the mechanical properties.

Secondly, a novel type of electrically conductive hot mix asphalt mixture utilizing carbon-based aggregate called coke aggregate was proposed and compared with electrically conductive hot mix asphalt mixtures using carbon fiber. The results showed that both types of electrically conductive hot mix asphalt mixtures had satisfactory mechanical performance, but utilizing coke aggregate could produce a higher heating efficiency and a lower material cost.

Last, electrically conductive geogrids such as carbon-glass fiber geogrids were utilized to explore their feasibility in electrically heated asphalt pavements for snow/ice melting based on prototype slab experiments. The results indicated that utilizing carbon-glass fiber geogrids effectively raised the pavement surface temperature at low temperatures and melted the snow in winter, which is a promising method of constructing electrically heated asphalt pavements.