Correlation between Deformation and Volumetric Characteristics in the Aging Condition of Hot Mix Asphalt

The surface layer of pavement structures tends to experience a decrease in performance as its service life approaches. Generally, this decrease in performance is caused by aggregate degradation and aging of the asphalt binder, which can be caused by traffic loads or weather exposure. The mechanical performance of asphalt mixtures is due to the effects of aggregate degradation, which was simulated by reducing the coarse aggregate fraction and adding medium and fine aggregate fractions. The asphalt aging process simulates changes in binder characteristics by adding RAP binder to Pen 60/70 asphalt. Hot mix asphalt (HMA) with new material (SA-1) as a control for degradation simulation (SA-2, SA-3 and SA-4). Marshall test results show that aggregate degradation significantly causes a decrease in voids in the mixture (VIM) and voids in mineral aggregate (VMA), as well as an increase in voids filled with asphalt (VFA). WTM test results show that HMA degradation causes an increase in rutting depth, which increases the deformation rate and decreases dynamic stability. The correlation results between WTM and Marshall tests show a negative exponential relationship between VIM and VMA with deformation and a positive exponential relationship between VFA and asphalt mixture deformation.