Extending the service life of asphalt concrete pavements through the addition of conductive metallic waste particles for induced crack healing

ABSTRACT This paper investigates the potential application of a metallic waste addition obtained from the cutlery industry to improve the electrical conductivity and allow crack healing of asphalt concrete mixtures through electromagnetic induction heating. The effects of three different metallic waste content on the physical and mechanical properties of asphalt concrete mixtures have investigated. The crack healing potential by electromagnetic induction heating has been assessed in fully and partially cracked asphalt concrete specimens to simulate preventive and corrective maintenance. The crack healing potential has been evaluated through the results of load versus displacement curves obtained through SCB tests, based on a fracture-based approach by the ratio of fracture strength recovery after electromagnetic induction heating. Potential benefits such as simple mixing process and the possibility of using habitual design methods with satisfactory physical and mechanical properties can be achieved by using 10% of metallic waste by volume of bitumen added to asphalt concrete mixtures. The addition of metallic waste modified the fracture behaviour of the asphalt concrete mixtures, which indicates that after crack healing, samples may present a loss of ability to resist crack propagation. Healing indexes of 0.77 and 0.83 obtained for fully and partially cracked specimens produced with 10% of metallic waste by volume of bitumen.