Self-healing capability of asphalt concrete with carbon-based materials

This study aims to investigate the effect of carbon-based materials, i.e., carbon fibers (CFs), carbon nanotubes (CNTs), and graphite nanofibers (GNFs), on the mechanical and self-healing properties of asphalt concrete. For this, 0.5% CF, CNT, and GNF, and 1.0% CF were incorporated, and plain asphalt concrete was also considered for comparison. The self-healing capability of asphalt concrete was examined based on induction heating and was quantitatively evaluated by comparing the flexural strengths of virgin and healed specimens. Test results indicated that adding the carbon nanomaterials, i.e., CNTs and GNFs, was more effective in improving the Marshall stability, indirect tensile strength, and dynamic stability, and reducing the porosity, compared to adding macro CFs. However, the flexural performance of asphalt concrete was more efficiently enhanced by adding the CFs relative to CNTs and GNFs. Asphalt concrete specimens that completely failed under flexure were partially self-healed using induction heating due to the incorporated carbon materials. The best healing capability, i.e., 40% recovery of the original flexural strength, was obtained for the specimens with 0.5% GNFs and CFs.