Enhancing Asphalt Pavement Durability: Evaluation of Encapsulated Soybean Sludge Rejuvenators for Self-Healing and Cracking Resistance

Self-healing of asphalt is a potential way to increase the service life of road surfaces. In the past, scientists have employed various methods to enhance the self-healing abilities of asphaltic materials. One of these methods is the application of encapsulated rejuvenating agents to initiate crack-healing by restoring asphalt binder to its initial attributes. The purpose of the current study is to evaluate the fracture resistance of asphalt mixtures and the crack recovery process, which is modified with encapsulated rejuvenating agent derived from waste, specifically soybean sludge (SS) and fatty acids extracted from soybean sludge (SSFA). Two different proportions (0.1 and 0.2) were used for the rejuvenator/water ratio (r/w) for each rejuvenator type and were meticulously examined for their influence on the physical and mechanical properties of the asphalt mixtures. Assessments of self-regeneration were conducted through semicircular bend (SCB) testing employing monotonic loading, measuring fracture resistance and the recuperation of fracture resistance during the postrest period. After this, the results showed that the introduction of capsules did not compromise the mechanical performance of the asphalt mixture, although it did influence crack behavior, resulting in a marginal strength reduction following crack healing. Despite the overall damage incurred, capsule inclusion facilitated the recovery of crack resistance and complete healing. Capsules achieved a peak recovery of 33% with a soybean sludge-to-water ratio of 0.1. Therefore, this study concluded the practicality of this approach and underscore the efficacy of soybean sludge as an encapsulated rejuvenating agent.