Laboratory Evaluation of Self-Healing Capability of Warm-Mix Asphalt Containing Calcium Alginate Capsules under Aging Conditions

Abstract

Pavement researchers have sought to develop more environmentally friendly asphalt that effectively mitigates the consumption of natural resources and maintenance costs. They have noted that using durable asphalt with improved self-healing can achieve these goals. Technologies like warm-mix asphalt or calcium capsules can help the economy and substantially reduce environmental impact. These aims can be attained with technologies such as warm-mix asphalt (WMA) and calcium alginate capsules. This study evaluates the effect of Sasobit, which is utilized as a typical modifier for WMA, long-term aging (LTA) and calcium alginate capsules on the self-healing performance and mechanical properties of asphalt mixture by using different tests such as resilient modulus, indirect tensile strength (ITS), fracture test on semicircular bending (SCB) specimens and edge notched disk bend (ENDB) specimens. According to Findings, long–term aging and Sasobit negatively affect the self-healing performance of mixtures, although capsules improve it. Also, ENDB specimens have lower healing values than SCB specimens; however, due to longer crack length, ENDB specimens have more capsules incorporated in healing performance compared to SCB specimens. As a result, this paper notes that the properties of asphalt binder not only have a great effect on the self-healing performance of the mix but also have a significant impact on the action of capsules on healing cracks.