Effect of Short-Term Aging Time on the Moisture Susceptibility of a Warm Mix Asphalt Binder Using the Surface Free Energy Method

摘要

The objective of this research was to investigate the moisture susceptibility of WMA after various aging time using surface free energy (SFE) method. The experiment design included the use of one binder and aggregate source, and two warm-mix additives (Sasobit and Evotherm) and four different rolling thin film oven (RTFO) aging times(0, 3, 5, 7 hours ). The sessile drop method was used in this study to measure the contact angle between asphalt binders and three probe liquids. From these measurements, the SFE components of the asphalt binders were determined using the Owens-Wendt method. The adhesion work, the debonding work and compatibility ratio (CR) of the aggregate-asphalt systems were calculated. The test result shows that the use of warm-mix additives can improve the adhesion work and CR while reducing the debonding work of control aggregate-asphalt systems after short-tem aging. Generally, the moisture susceptibility of WMA binder is less than that of asphalt without WMA additive in the same short-term aging time.