Analysis of different indices for high- and low-temperature properties of asphalt binder

Abstract

The high- and low-temperature performance of asphalt binders have an important effect on the rutting and cracking resistance of asphalt pavements, thus these are two of the most important performance of asphalt binders. Nowadays, there are many indices to evaluate the high- or low-temperature performance of asphalt binders respectively. But there is still no unified option about which index is better.As a kind of typical viscoelastic materials, both of the high-temperature performance and the low-temperature performance of asphalt binders are related to viscoelastic characteristics of asphalt binders, but they are opposite to each other. That is, a binder needs to have more elastic part for high-temperature performance but more viscous part for low-temperature performance. So the ratio of viscous part to elastic part is important to high- and low-temperature performance of asphalt binders. Based on that thought, a new index based on viscoelastic characteristics, referred to as RJ, is developed in this study. Different high- and low-temperature evaluation indices including RJ were analyzed by comparing the performance ranking evaluated by them with the ranking of the corresponding mixtures. The correlation between performance of binders evaluated by different indices and the performance of the corresponding mixtures were also analyzed. Based on the results, zero shear-rate viscosity and non-recoverable stiffness is found to be suitable for evaluating the high-temperature performance of asphalt binders, stiffness at 60s from BBR is found to be suitable for evaluating the low-temperature performance of asphalt binders. The established evaluation index, RJ, is found to be suitable for evaluating both performances of asphalt binders.