Volumetric and Mechanistic Characteristics of Asphalt Mixes Containing Recycled Asphalt Pavement

Abstract

This study explored the potential of using up to 40% of recycled asphalt pavement (RAP) in Oklahoma mixes by determining the change in volumetric and mechanistic (namely, dynamic modulus and creep compliance) characteristics with the addition of RAP. One RAP source was used to study the change in volumetric and mechanistic characteristics on Superpave mix (Oklahoma S3) with a nominal maximum size (NMS) of 19 mm. A total of two mixes containing 25% RAP and the other containing 40% RAP, were designed and tested. It was found that the voids in mineral aggregate (VMA) and voids filled with aggregate (VFA) of the RAP mixes increased with increasing percentage of RAP. The creep compliance results showed an increase in the stiffness and a reduction in compliance of the mix due to increase in the RAP content. The dynamic modulus test results illustrated that the asphalt mix containing a higher amount of RAP have higher dynamic modulus values.