Long-term effectiveness of vegetable-based rejuvenation agents across different aging stages of asphalt pavements

Abstract

ABSTRACT The effectiveness of rejuvenation agents in reducing the stiffness of aged binder in Reclaimed Asphalt Pavement (RAP) material during the initial service life is well documented. However, their long-term efficacy remains under evaluation. This is partially due to the wide variety of rejuvenation agents, with varying chemical compositions, which impact the short- and long-term performance of the rejuvenated material. This paper addresses this concern by assessing the effectiveness of five types of vegetable-based rejuvenation agents across the ageing stages of asphalt mixtures during the service life of flexible pavements. The evaluation includes monitoring the rheological, chemical and performance-related properties of the rejuvenated binder blends (i.e., a combination of aged asphalt binder, virgin asphalt binder and rejuvenator) as ageing progresses. The results indicate that the benefit of rejuvenation decreases with time and that this reduction is a function of the type of rejuvenator. These results highlight that an appropriate selection of a rejuvenator should consider not only the improvement of the material during the production of the mixture and a good response and performance in the initial stage of the pavement operation, as is often the case, but also its capability to maintain these positive effects in later stages of its service life.