Characterisation of aged rejuvenated bitumen using master curve approach

Abstract

Recycling asphalt pavement (RAP) is a sustainable approach to pavement construction, reducing waste and conserving natural resources. However, RAP contains aged binders that require restoration to regain optimal rheological properties. Rejuvenators play a key role in modifying these binders, helping them meet specific performance requirements. Current practices involve using bitumen of particular grades, with or without rejuvenators, depending on the proportion of RAP being recycled. Determining the appropriate rejuvenator dosage is essential for maximizing RAP utilization while maintaining the desired binder characteristics. This study investigates the rheological performance of unmodified and polymer-modified binders under different aging conditions and rejuvenator concentrations (0–12%) using a dynamic shear rheometer. The results show that aging significantly alters mechanical properties of bitumen, while rejuvenators enhance viscosity and restore rheological behavior. These findings underscore the importance of proper rejuvenator application in RAP recycling, ensuring improved binder performance and sustainability in asphalt pavement construction.