Rheological behavior of bio-asphalts and effect of rejuvenators

Bio-binders are considered as a sustainable alternative to the current asphalt binders. Various biomass resources have been investigated to produce dependable bio-binders by different researchers. While bio-binders and their blends with asphalt binders show promising high-temperature properties, their properties deteriorate rapidly with progress in aging, raising valid concerns about their cold-temperature performance. Most studies address this problem by minimizing the bio-binder content. This study was conducted to evaluate rheological behavior of bio-asphalts with high bio-binder content, and to validate a recently proposed method for improving long-term performance properties of bio-asphalts by inclusion of small quantities of rejuvenator. Samples of different bio-asphalts with 35% replacement ratio were prepared, and were consequently modified by small rejuvenator content. Results showed that the proposed method can successfully alleviate most concerns about the long-term properties of bio-asphalts. However, it was found that all bio-asphalts have lower resistance against fatigue and non-load related cracking. (C) 2020 Published by Elsevier Ltd.