Reclaimed asphalt pavements (RAP) have been called one of the most recycled materials in the world. Pavements mixed with RAP would be milled or excavated when they reach the end of service life. The reuse of RAP makes it as a second RAP, and is referred as R 2 AP in this study. R 2 AP was added at ten levels to hot-mix asphalt mixtures (HMA) with four different recycling agents in the laboratory. Adding 40% R 2 AP did not appear to alter the mixture properties dramatically. When the percentage was higher than 40%, the aged binder in R 2 AP created a significant change in the mixture properties. All the mixtures showed an increase in energy loss with an increase in R 2 AP percentages. The higher energy loss in the R 2 AP mixture indicated a higher possibility of moisture-induced damage. There should be a limit on percent R 2 AP that could be incorporated into HMA.

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