Research on the effects of asphalt performance on rutting resistance and its correlation with rutting performance indicators

The rutting development of asphalt pavement is generally divided into two stages including the initial densifi-cation and the shear slow. The rutting resistance of asphalt mixture is greatly affected by the performance of asphalt. However, the effects of asphalt performance on the different rutting development stages are not fully clear. This paper is aimed to evaluate the applicability of rutting performance indicators to asphalt performance and further identify the correlation of changes in asphalt performance with rutting development stages. The rutting tests were carried out to study the effect of asphalt performance on the rutting resistance, in which the asphalt grade, modifier type and content, and asphalt type were involved. The dynamic stability (DS), complex stability index (CSI), Tseng-Lytton (A/C), and Gladkikh (1/E) models were selected as the rutting performance indicators. Results of the rutting test show that the application of low-grade asphalt and modifier has a larger reduction in the rutting depth. The polyethylene (PE) modifier has the largest contribution to the rutting resistance and a better composite modified effect with the styrene-butadiene-styrene (SBS) modified and 30# asphalt. The asphalt mixtures with low-grade and crumb rubber (CR) modified asphalt have the lowest tem-perature sensitivity. Furthermore, the asphalt performance has great effects on the initial densification stage, as well as the shear slow stage. The A/C and CSI that are related to both the initial and secondary rutting stages are the most reliable indicators to characterize the effect of asphalt performance on the rutting resistance of asphalt mixture. The correlations of DS and 1/E with the rutting depth are lower than the former two indicators, indicating that these only related to the secondary rutting stage are not recommended.