Effect of moisture diffusion on the properties of rubber-modified asphalt and aggregate interface considering multiple influencing factors

• Published in: Construction & building materials 2024-10, Vol.449, p.138358, Article 138358
• Main Authors: Chen, Siting, Lu, Lei, Gao, Ya, Yin, Chaoen, Prodhan, Md Sumon, Zhou, Xinxing, Zhang, Xiaorui
• Format: Article
• Language: English
• Subjects: Moisture diffusion; Molecular simulation; Multiple influencing factors; Rubber-modified asphalt and aggregate interface
• ISSN: 0950-0618
• DOI: 10.1016/j.conbuildmat.2024.138358

Moisture-induced degradation is an inherent phenomenon at the interface between rubber-modified asphalt and aggregate, moisture ingress through diffusion impairs the integrity of this interface. This study employed molecular simulation to assess the performance of the rubber-modified asphalt and aggregate interface, considering multiple influencing factors such as temperature and loading. Infrared spectroscopy served to validate the alterations in functional groups after moisture exposure. Quantitative metrics, including mean square displacement, interfacial adhesion energy, adsorption energy, radius of gyration, solubility parameter, and molecular orientation, were computed to pinpoint the moisture-induced degradation zones. The findings demonstrated that the maximum moisture diffusion rate subject to various influencing parameters occurred at 298 K and 3 atm, as well as 333 K and 3 atm. Temperature exerted a more profound influence on the rubber-modified asphalt-aggregate interface compared to loading. The strength of hydrogen bonding between moisture and rubber molecules surpassed Van der Waals forces and induction force. Infrared spectroscopy showed that the diffused moisture persisted within the interface. •The moisture-induced degradation zone was successful marked.•The temperature effect on the interface was greater than that of loading.•H-bond force stronger than Van der Waals force and induction force was proposed.