Rheological and chemical evaluation of aging in 100% reclaimed asphalt mixtures containing rejuvenators

Rejuvenators improve the performance of reclaimed asphalt mixtures but relatively little is known about their long-term aging characteristics. This study evaluated the effect of four different rejuvenators on aging characteristics of 100% reclaimed asphalt mixtures. Rheological tests on extracted bitumen revealed that tall oil-based rejuvenator showed highest reduction and petroleum-based rejuvenator showed lowest reduction in stiffness of binder in the long term. At lower strain levels, the fatigue life calculated from linear amplitude sweep test was significantly higher for long-term aged binder compared to unaged binder due to increase in stiffness of bitumen. All the rejuvenated binders showed rutting performance comparable to that to virgin binder. Fourier transform infrared spectroscopy showed increased carbonyl peak intensity after long-term aging, but no clear implications were made for effect of aging on sulfonyl index.