Ageing behaviour of naturally and artificially aged bitumen samples after the addition of rejuvenators

Abstract

Reusing bitumen and asphalt is an approved practice, but the efficiency highly depends on adding virgin bitumen. Rejuvenators have gained increased importance in reaching independence from crude oil and exploring possibilities of multiple reuses. However, rejuvenators are often tested and evaluated exclusively on artificially aged bitumen samples. Therefore, the main objective of this publication is to investigate the rejuvenation of Reclaimed Asphalt Pavement (RAP) binders using three RAP samples and three rejuvenators. Rheological material properties, chemical effects of rejuvenation processes and the ageing behaviour after rejuvenation are examined. The results are further compared to rejuvenated artificially aged bitumen. It has been found that the rejuvenators reveal varying degrees of impact on RAP binders and artificially aged bitumen samples, as artificially aged bitumen samples tend to show fewer ageing changes than the RAP binders. Moreover, also the ageing behaviour of the pure rejuvenator influences the success of reuse.