Laboratory investigation on electrical and mechanical properties of asphalt mixtures for potential snow-melting and deicing pavements

This study aims to develop electrically conductive asphalt (ECA) mixtures utilizing carbon fiber and/or graphite for potential snow/ice-melting pavements without compromising the mechanical properties. The results showed that an electrical resistivity of 0.7–2.7 Ω·m could be potentially used as the design resistivity of ECA mixtures. 6 mm was the optimum length of carbon fiber for improving electrical conductivity. The ECA mixtures had a comparable or higher Marshall stiffness and indirect tensile strength than the control mixture. Adding carbon fiber alone significantly improved the cracking resistance of single-phase ECA mixtures, while the cracking performance of two-phase ECA mixtures was highly affected by the combinations of carbon fiber and graphite. Four ECA mixtures could meet the design resistivity requirement, while only one single-phase ECA mixture containing 6 vol% (by volume of binder) carbon fiber and one two-phase ECA mixture made with 3 vol% carbon fiber and 15 vol% graphite did not impair the cracking resistance.