Exploring the Use of Reclaimed Asphalt Pavement in Airfield Surface Mixes: Insights from the Mixture and Binder Scales

Even though reclaimed asphalt pavement (RAP) has been extensively used in highway surface layers, its use in airfield pavement surfaces has been limited. This study explores the potential of using RAP by evaluating airfield hot mix asphalt (HMA) mixtures containing RAP at both the mixture and binder scales. Three laboratory-produced HMA mixtures, one control and others with 10% and 30% RAP, were designed according to the Federal Aviation Administration’s advisory circular 150/5370-10H. Typical mix performance tests were conducted, while binder tests involved the use of the poker chip test and other non-specified tests. As expected, rutting resistance was improved by including RAP, while cracking resistance decreased, with concern about mixes with higher amounts of RAP. The Illinois Flexibility Index Test sample’s fractured surface image analysis revealed that cohesive failure of the binder is the primary factor contributing to HMA mixture cracking while using RAP, assuming the same base binder and anti-stripping agent are utilized. The mixture testing framework, along with binder testing, has been shown to be effective for designing airfield mixes with RAP and serves as a baseline for future specifications.