Extrinsic healing of asphalt mixtures: a review

When exposed to climate effects, the stiffness of the bitumen increases, decreasing its relaxation capacity and making the binder more fragile, promoting microcracks formation and cracking due to traffic. Effective maintenance strategies are necessary to ensure longevity and minimise the need for rehabilitation. Addressing the material’s durability is one efficient solution to extend the service life of roads. Extensive research has been conducted to explore methods of increasing pavement life, focusing on healing bitumen and asphalt mixtures. Healing mechanisms offer the promise of improved lifetime and enduring strength by eliminating microscopic damage that can lead to failure over time. In the context of asphalt pavements, healing techniques using nanoparticles, induction heating, microwave heating, and healing agent have shown promise. This paper provides an overview of healing performance and technologies employed in asphalt materials, offering insights into the potential for extending their service life and promoting sustainability in road infrastructure.