Comparing the Effect of Moisture on Different Fatigue and Cracking Behaviors of RAP–WMA.

The main objective of this study is to investigate the effect of moisture damage on the fatigue and cracking behaviors of warm mix asphalt (WMA) containing reclaimed asphalt pavement (RAP). To achieve this aim, different fatigue and cracking tests such as indirect tensile fatigue failure, four point beam fatigue, and semicircular bending tests have been conducted, and several parameters have been obtained. These parameters include tensile strength ratio (TSR) and fracture energy ratio (FER), indirect tensile fatigue ratio (IDTR), peak load ratio (PLR), J-integral ratio, and flexibility index (FI), and Nf and flexural stiffness ratios. The results showed that moisture-damaged RAP-WMA demonstrated slightly weaker fatigue and cracking resistance than other mixtures, which is not significant considering the environmental advantages of the mixture. Hence, RAP-WMA would be a proper and beneficial alternative as pavement material where there are significant problems in supplying natural aggregates, and issues like moisture damage and being environment friendly are big concerns. Also, it has been concluded that the fatigue test condition (stress and strain control modes) had a significant effect on the moisture damage investigation. [ABSTRACT FROM AUTHOR]