ABSTRACT
The degree of binder activation of reclaimed asphalt pavement (RAP) is a critical aspect the design of the recycled asphalt mix-tures. Assuming RAP binder activation of less than 100% insinuates that part of the RAP binder will be inactive in the mixing process. It is im-portant to comprehend if there is any difference between the active and the inactive binder as the recycling agent to be used could be chosen con-sidering only the active binder characteristics. The objective of this study is to evaluate aging differences within different RAP binder layers. Stages of binder extraction were performed on two different RAP materials in order to simulate different binder activation levels. After each ex-traction, the binder recovered was evaluated in terms of its rheological properties and the saturate-aromatic-resin-asphaltene (SARA) fractions. The results imply that the outer layer (external RAP binder layer) is more oxidized as compared to the inner layer (binder close to the aggregate). This indicates that the more oxidized RAP binder will be available to be blended. Keywords: RAP, recycled asphalt mixture, aging, SARA
