Evaluation of bio-materials' rejuvenating effect on binders for high-reclaimed asphalt content mixtures

The interest in using bio-materials in pavement engineering has grown significantly over 10 the last decades due to environmental concerns about the use of non-recoverable natural resources. In 11 this paper, bio-materials are used together with Reclaimed Asphalt (RA) to restore some of the 12 properties of the aged bitumen present in mixtures with high RA content. For this purpose, two bio-13 materials are studied and compared to conventional and polymer modified bitumens. Blends of these 14 materials with RA bitumen were produced and studied to simulate a 50% RA mixture. The rejuvenating 15 effect of the two bio-materials on RA has been assessed and compared with the effect of the conventional 16 binders. Apparent Molecular Weight Distribution of the samples (obtained by the δ-method) and 17 different rheological parameters were used for this purpose. Results revealed the power of bio-materials 18 to rejuvenate RA bitumen, showing their capability to be used as fresh binders in high-RA content 19 mixtures.