Conductive asphalt concrete: A review on structure design, performance, and practical applications

Conductive asphalt concrete can be used to help pavement snow melting/deicing by an asphalt pavement electrical heater. It is an emerging technology to ensure safety driving during winter time. Based on the Joule heating law, an electric current passing through the conductive asphalt concrete (a conductor) could generate enough heat to prevent snow accumulation and icing on the asphalt pavement surface. This article provides a review on the material design, construction technique, performance evaluation, and engineering applications of conductive asphalt concrete. The literature shows that the conductivity and mechanical properties of conductive asphalt concrete are strongly dependent on the material compositions and mixing programs. Meanwhile, the mechanism of conductivity improvement is identified according to the characteristics of conductive additives. In addition, the effects of service conditions on the resistivity are evaluated. Asphalt pavement electrical heater technique shows some appreciable advantages in environment protection and traffic safety aspects, although it has few applications in the highway industry. It therefore recommends that further investigations on asphalt pavement electrical heater are indispensable and should focus on some covered issues besides the existing research, such as proper material selection, resistivity stability, desirable high operational efficiency, and suitable construction technique.