Performance of Hot-Mix Asphalt with Fractionated Reclaimed Asphalt Pavement Content

Abstract

Usage of reclaimed asphalt pavement (RAP) material can have economic and environmental benefits. However, the variability in RAP sources and the uncertainty in long-term performance tend to limit the use of RAP content in asphalt mixtures to 20% of the mixture or less. RAP fractionation is one of numerous methods that have been proposed to increase RAP usage. RAP fractionation into fine and coarse stockpiles aims to improve the consistency of RAP particle sizes as well as binder content and properties to maintain an acceptable mix design and performance. The objective of this study is to characterize the performance of mixtures containing fractionated RAP content for local materials in Manitoba. Cracking and rutting performance of hot-mix asphalt mixes were assessed using Illinois Flexibility Index Test and Hamburg wheel-tracking test, respectively. Results showed that resistance to rutting increased with the increase of RAP content. Cracking resistance decreased with the incorporation of RAP. Additionally, fractionated RAP samples showed better resistance to cracking and rutting than unfractionated RAP samples. The final findings of this research will help transportation agencies in Manitoba to optimize the design of asphalt mixtures containing RAP.