Effect of ageing and RAP content on the induction healing properties of asphalt mixtures

Over the service life of asphalt roads, different factors produce, in the bitumen, a hardening process known as “ageing”. Also, the addition of recycled, aged material (i.e. RAP) to new mixes modifies the viscosity of the mix. The present research studies how these two actions affect the capacity for healing, by electromagnetic induction, of asphalt mixes. Mixes subjected to different ageing processes or containing different amounts of RAP were tested. Results show that both ageing, and RAP content contribute to increasing binder stiffness and air voids content in the mix. Therefore, the healing process becomes less effective and energy efficient.