A laboratory investigation on benefits of WCO utilisation in asphalt with high recycled asphalt content: emphasis on rejuvenation and aging.

Waste cooking oil (WCO) is being investigated as a rejuvenator to utilise higher amount of reclaimed asphalt pavement (RAP) in asphalt mixtures. Past studies have evaluated the potential of WCO as rejuvenator without considering the performance of the rejuvenated binder after the secondary aging (long-term aging). The studies did not reveal any optimum amount of WCO required for the appropriate rejuvenation for incorporation of particular amount of RAP binder or aged binder. In this study, the potential of WCO is evaluated as rejuvenator of the binders incorporating higher aged binder by considering the anti-aging effect of WCO on the performance of rejuvenated binder after secondary aging. The study proposes a concept to determine the optimum dose of WCO for binders with different percentage of aged binder based on Equi-viscous concept and rutting criteria for short-term aged binder.Optimum dosages for the rejuvenated binders with 45, 60 and 75% RAP binder were found to be 6.45, 7.07 and 7.59%, respectively. The rejuvenated binders with different RAP contents and optimum WCO dosage showed lower susceptibility against fatigue and rutting. Further, the study concludes that the WCO can perform dual function as rejuvenator and also as an anti-aging additive. [ABSTRACT FROM AUTHOR]