Development of Autonomous Setup for Evaluating Self-Healing Capability of Asphalt Mixtures

Asphalt mixtures have self-healing capabilities, yet most self-healing investigations are carried out with complex and time-consuming fatigue tests. To investigate the self-healing capability in a simple, efficient manner, a beam-on-elastic-foundation (BOEF) test setup was proposed. With a notched asphalt concrete beam fully glued to a low modulus rubber foundation, the BOEF setup was able to control the self-healing process autonomously, including crack closure and healing at different rest periods and temperatures. A load crack opening displacement curve was used for characterizing the self-healing capability of the monotonic response with a loading–healing–reloading procedure. In addition, small numbers of dynamic loads were also applied to the BOEF setup under different cracking and healing conditions. An apparent modulus of the BOEF asphalt beam was obtained on the basis of the dynamic response of the load crack opening displacement. The results indicate that the self-healing capability obtained in the monotonic tests depends on the healing time and healing temperature. The healing temperature has the larger effect of the two. Most of the apparent modulus of the BOEF asphalt beam recovers at the beginning of the self-healing process. The influences of healing time and temperature are limited. As a result, the BOEF setup is proved as a potential tool for the self-healing investigation of asphalt mixtures.