Effect of aggregate damage on self-healing characteristics of asphalt concrete: An image processing-based method

• Published in: Construction & building materials Vol. 425; p. 135924
• Main Authors: Atakan, Mert, Yıldız, Kürşat
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 26.04.2024
• Subjects: Adhesive failure; Broken aggregate; Cohesive failure; Fracture-based healing test; Image processing; Self-healing asphalt; Self-healing asphalt; Cohesive failure; Fracture-based healing test; Image processing; Broken aggregate; Adhesive failure
• ISSN: 0950-0618; 1879-0526
• DOI: 10.1016/j.conbuildmat.2024.135924

In the fracture-based healing test, asphalt specimens generally break into two halves and the aggregates in the crack path also break. In this study, the effect of aggregate damage on the self-healing performance of asphalt concrete was studied. To achieve this, semi-circle asphalt specimens were produced. Then, they were broken using the Semi-circle bending test (SCB) at different temperatures (i.e., −20, −10, 0, 10, and 20 °C) to create various aggregate damage situations. Next, the fracture surfaces of specimens were photographed and the percentages of damage types (i.e., adhesive, cohesive, and broken aggregates) were obtained by using image processing techniques. After the specimens were healed at a constant 55 °C, the SCB test was applied again to measure the strength of the specimens and to calculate healing performance. Finally, fracture surfaces were photographed again. According to findings, as breaking temperatures increase, broken aggregates and adhesive damage decrease. Cohesive damage, on the other hand, rose with the high breaking temperature. Healing performance was better at low breaking temperatures. A positive correlation was found between aggregate damage and healing levels, but it was explained as a spurious relationship. The real correlation was negative which was obtained from a second dataset. •An image processing method was used to obtain broken aggregate percent in fracture surfaces.•Various aggregate damage percentages were created by using different breaking temperatures.•The drawback of using different breaking temperatures was explained.•Healing performance was better at low breaking temperatures.•A negative correlation was determined between aggregate damage and healing levels with an additional dataset.