The determination of mechanical performance of laboratory produced hot mix asphalt mixtures using controlled RAP and virgin aggregate size fractions

This study investigates the influence of fractionated reclaimed asphalt pavement (RAP) materials on asphalt mixture performance. The RAP mixture percentages used were 15%, 35%, and 50% in the study. The amount of RAP materials recycled within hot mix asphalt (HMA) drum plants are typically no more than 30% RAP. Asphalt pavement analyzer (APA) rutting, modified Lottman, and dynamic modulus testing were conducted on the RAP and virgin aggregate blended asphalt mixtures. On average between all RAP mixtures, the addition of RAP decreased rutting by 24%, and increased resilient modulus by 52% due to the addition of RAP asphalt binder and aggregates; which stiffen the mixture under higher temperature and heavier loading conditions. Dynamic modulus results indicated a statistical significant difference for high percentage RAP mixtures.

► RAP mixtures with fractionated controlled size fractions are analyzed. ► Asphalt pavement analyzer (APA) rutting, modified Lottman, and dynamic modulus testing were conducted. ► T-test analysis shows RAP dynamic modulus performance variability is significant.