Moisture Susceptibility in Warm Mix Asphalt Mixtures: Influence of Aggregate Type, Binder Grade, Additive Type, Compatibility and Evaluation Methods
摘要
One of the most critical factors influencing the durability and performance of asphalt pavements is failure due to moisture damage. Although Warm Mix Asphalt (WMA) technologies offer clear advantages such as reduced production temperatures and lower environmental emissions, concerns persist regarding the increased susceptibility to moisture arising from complex binder–aggregate–additive interactions. The roles of aggregate type, binder grade, and additive type are crucial, as each can impart both positive and negative effects on overall pavement performance. Moreover, variations in production temperatures, binder oxidation, and moisture conditioning protocols can significantly influence the moisture-induced damage behaviour of asphalt mixtures. This review compiles and discusses studies that examine the effects of aggregate mineralogy, binder grades, additive types, and dosages on the compatibility of WMA modified mixture impacting their moisture resistance. It also highlights several drawbacks in the conventional evaluation techniques and propose innovative approaches to understand the aggregate-binder-additive compatibility as well as moisture evaluation techniques. Furthermore, this review emphasizes the importance of linking multiscale investigations such as binder composition, nano-scale-adhesion and debonding behaviour with macroscale performance parameters. Overall, the review provides insights into the evaluation of different materials that promote better aggregate–binder–additive compatibility, identifies critical research gaps and limitations, and offers recommendations to enhance future evaluation methodologies and guide continued research on moisture susceptibility in WMA and other modified asphalt mixtures.
Graphical Abstract