The influence of asphalt rheological behavior and durability of recycled asphalt concrete under high viscosity rap and high addition

This study performs laboratory investigation to discover the rejuvenating effect of Rejuvenating Agent (RA) on the performance of aged asphalt binder and asphalt concrete in order to increase Recycled Asphalt Pavement (RAP) usage. It also distinguishes between asphalt binder employing viscosity blending chart from AI MS-2, and penetration grade from Japanese blending chart, to find the optimum necessary RA in the blends and therefore solve the rutting problem. The material used was 20% and 40% of a 100,000 poises Recycled Asphalt Binder (RAB) with AC 20 as virgin binder and RA. Control samples, short-term aging, and long-term aging samples were used to describe the durability of the mixtures. Penetration blends decreased the RA needed about 40% compared to the viscosity blends and showed better rutting performance, especially for a higher percentage of RAP. Viscosity blending yielded a misleading in the addition of RA and resulted in softer RAB, which is susceptible to rutting. Thus, for the case of rejuvenating severely aged and quite high content of RAP mixtures, relying on only viscosity test and AI MS-2 is not adequate.