Self healing behaviour of asphalt mixture has been known for many years. This unique behaviour can help asphalt concrete to recover its strength after damage. Healing can also extend the service life of asphalt pavements. A beam on elastic foundation test setup (BOEF) was developed to investigate the self healing behaviour of asphalt mixture in a controlled and effective way. Within this setup, a notched asphalt beam was glued on a low modulus rubber foundation, and a symmetric monotonic load was applied with loading-unloading-healing-reloading cycles. The experimental results indicate the existence of the healing behaviour. Increasing reloading curves are observed for increasing healing time and healing temperatures. In order to further understand the cracking and healing phenomenon, a finite element simulation was carried out with a smeared crack cohesive zone model (CZM). By defining both properties of the bulk asphalt mixture and the cohesive zone, the global load-crack opening displacement (COD) response during cracking and healing process was simulated successfully. The model is also capable to separate the two healing phases including crack closure and strength gain. It is also shown that further implementation of the cracking and healing modelling of asphalt mixtures is important for durable asphalt pavement.
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