Aging of Rejuvenated Asphalt Binders

Abstract

An important concern that limits the RAP content in asphalt mixtures is the fact that the aged binder that is present in the RAP can cause premature cracking. Rejuvenators are frequently added to high RAP mixtures to enhance the properties of the binder. There is no existing method to predict the longevity of a rejuvenated asphalt. This study investigated the aging of rejuvenated binders and compared their durability with that of virgin asphalt. Various samples with different types and proportions of RAP, virgin binder, and rejuvenator were aged by RTFO and three cycles of PAV. DSR and BBR tests were conducted to examine the high-temperature and low-temperature rheological properties of binders. Results indicated that the type and dosage of the rejuvenator have a great influence on the aging rate and durability of the binder. Some rejuvenators make the binder age slower, while others accelerate aging. These observations confirm the importance of evaluating the long-term aging of recycled binders. For this purpose, critical PAV time was proposed as a measure of binder’s longevity.

Influence of Laboratory Long-Term Aging on Selected Fracture Parameters of Asphalt Mixtures

“…Guangji Xu et al (2018) used molecular dynamics to study diffusion of rejuvenators into bitumen. The results of this study indicate that simulations by molecular dynamics have the potential to calculate inter-diffusion coefficient and thermodynamic properties of bituminous binder [ 7 ].…”

“…The oxidation causes irreversible (or only very hardly reversible) changes in binder´s characteristics and adversely affects pavement service life. The behavior of asphalt mixture depends mainly on the behavior of bituminous binder [ 4 , 5 , 6 , 7 , 8 , 9 ].…”

A Review on the Durability of Recycled Asphalt Mixtures Embraced with Rejuvenators

“…Mohammadafzali et al [27] examined the long-term performance of two commercial rejuvenating agents on rheological properties of aged asphalt. The rejuvenators were heavy paraffinic oil with high aromatic content (R1) and a re-refined product, which is a semi-solid substance (R2).…”

“…Meanwhile, some rejuvenating agents are susceptible to oxidation. In order to achieve high RAP mixture with durability similar to that of new pavement material, rejuvenated asphalt should not age faster than VA [27].…”

Recyclability potential of asphalt mixes containing reclaimed asphalt pavement and industrial by-products

“…In this sense, most recent studies attempt to characterise the effect that age has on the performance of these asphalt mixes, not to assess their reuse once the end of their useful life is reached [43][44][45][46][47][48].…”