CONSTRUCTION AND BUILDING MATERIALS, vol.262, 2020 (SCI-Expanded)
The paper aims to evaluate the usability of fly ash (FA), which is an environmental pollutant, as a filler in asphalt concrete in order to accelerate its microwave heating rate to promote self-healing. In the study, microwave heating rates of asphalt concrete specimens with and without FA were determined via thermographic imaging. Then the three-point bending test was applied to specimens before and after the microwave healing procedure. The crack size of the damaged specimens was also measured via a crack microscope in order to determine the effect of damage levels on microwave healing performance. Test results demonstrated that crack sizes both before and after healing could be interpreted as an indicator of the self-healing performance of the specimen. Microwave heating temperature is the key factor of self-healing, and FA has improved microwave heating rate of asphalt concrete. FA has also improved the healing capability of specimens at some damage levels. It can be concluded that fly ash has great potential as a filler in self-healing asphalt concrete because it can improve self-healing and mechanical characteristics of asphalt concrete, and FA could be reclaimed by using this way. (C) 2020 Elsevier Ltd. All rights reserved.