Phase-Transition Temperature of Asphalt Materials Based on DMA

Abstract

Asphalt materials including binder, mortar, and mixture are extensively used in the field of pavement engineering due to their obvious viscoelastic properties. To study the phase-transition temperature (Tp) of asphalt materials, we apply dynamic mechanical analysis (DMA) to conduct several temperature-sweep mode tests and compare the Tp values among these materials with similar sizes. Meanwhile, 27 AC5 mixtures are tested to determine the impact of binder type, gradation, and binder content on Tp. Results indicate that the Tp of binder and mortar is negative, but that of mixture is positive. Good correlations among Tp of binder, mortar, and mixture with the same binder type are observed, showing that binder quality is the key factor affecting Tp. Gradation type also affects Tp, and the mixture with a finer gradation has a lower Tp. Among the AC5 asphalt mixtures, the Tp of AR mixture is lower than those of the others, thereby demonstrating better low-temperature performance.