Effect of Rejuvenator on Performance Properties of WMA Mixtures with High RAP Content

The production of warm mix asphalt (WMA) mixtures with high percentages of reclaimed asphalt pavement (RAP) is gaining attention as a way to save costs and efficiently utilize existing resources. However, WMA must perform at least as well as hot mix asphalt (HMA) before it can be used as a replacement for HMA. In this study, the performance of a WMA mixture with a high percentage of RAP (40 % RAP) and a WMA additive (1.5 % of binder weight) that works as a rejuvenator was evaluated and compared with the performance of a HMA mixture with the same amount of RAP in order to evaluate the effects of the WMA rejuvenator. These mixtures were evaluated in terms of fatigue cracking using the simplified viscoelastic continuum damage (S-VECD) model and in terms of rutting using the triaxial stress sweep (TSS) test. In addition, layered viscoelastic pavement analysis for critical distresses (LVECD) was used to predict the fatigue resistance of these mixtures for future use. The WMA rejuvenator was found to improve the mixing and compaction ability of the WMA mixture. Also, compared to the HMA mixture, the WMA mixture showed better fatigue resistance, but the rejuvenator found to have an adverse effect on the rutting resistance of the mixture.