High Temperature Performance Evaluation of High Viscosity Asphalt at Different Aging Degrees Based on Multiple Stress Creep Recovery Test

Abstract

Abstract In order to investigate the effect of high temperature on the performance of three high viscous asphalt in company with various aging degrees (ADs), multiple stress creep recovery (MSCR) test was employed. CRR and irrecoverable compliance were also carried out to measure the high temperature resistance of high viscous asphalt to external loading in the presence of various aging conditions (ACs) as well as to examine the sensitivity of high viscous asphalt towards the stress. The findings of the study demonstrated that after short- and long-term aging, the high-viscosity asphalt turned harder. Also, type I high-viscosity asphalt was observed to have the greatest deformation resistance acted upon by various stress fields and ACs. Furthermore, in company with various ACs, while the average creep recovery rate (CRR) of Type I and Type II high-viscosity asphalt was found to be higher than that of the SBS modified asphalt, the average irrecoverable compliance was observed to be smaller. This indicated the significant effect of high-viscosity modifiers on the improvement of the elastic recovery performance of asphalt and its resistance to high temperature flow deformation. Contrary to the order of their CRRs, the magnitude of stress sensitivity of the three high-viscosity asphalt at various ADs was observed to be type II < type I < SBS modified asphalt, indicating a good negative correlation between stress sensitivity and average CRR. Furthermore, the obtained results revealed that, in the presence of various ACs, the high temperature viscoelastic qualities of high viscosity modified asphalt is considered by the MSCR test. Also, to comprehensively evaluate the high temperature performance of high viscosity modified asphalt at various Ads, the use of such indexes as the average CRR, average irrecoverable compliance and stress sensitivity coefficient were essential.