Infrastructure is Failing—But These Roadway Material Innovations Could Help

Material scientists are stepping in to help. A collection of new technologies promises to replace conventional bitumen with self-healing asphalt. For example, scientists at the Delft University of Technology in the Netherlands have created such a material by infusing asphalt with electrically conductive fibers and fillers in the configuration of closed-loop circuits. When a current is introduced near a crack, the heat generated within the circuits melts the bitumen and seals it. Similarly, researchers from ETH Zurich and the Swiss research organization Empa developed an approach in which they inject iron oxide nanoparticles into surface cracks. Once this patch material is exposed to an alternating magnetic field, the surrounding asphalt softens and heals itself—a process that only requires a few seconds per patch.