- “Towards a better assessment of recycling agent effects on bitumen during hot recycling” doi link

Auteur(s): Lahjiri Faycal, Gazeau Sabine, Delfosse Frederic, Dony Anne, ZIYANI Layella, Mouillet Virginie, Henn F.

Ouvrage: Springer (2019) 33-43

Ref HAL: hal-02447142_v1
DOI: 10.1007/978-3-030-29779-4_4
Exporter : BibTex | endNote

The current challenge is to produce asphalt mixtures incorporating higher rates (>50%) of Re-claimed Asphalt (RA) while controlling the quality of the final mix. During the service life of a pavement properties change, mainly due to oxidation and need to be restored. The resulting mix must exhibit at least equivalent performances regarding the mechanical and durability properties compared to that from a mix without RA. Hence, recycling agents are sometimes employed to “rejuvenate” aged bitumen. In this study, three recycling agents were used on both RA and neat bitumens, displaying different compositions. The effects on unaged and aged blends were as-sessed through rheology tests using Dynamic Shear (DSR) and Bending Beam (BBR) Rheome-ters. Data from DSR obtained with 4mm and 8mm parallel plates allowed to calculate the Glov-er-Rowe criteria and to determine the crossover parameters whilst BBR measurements yield Tm, Ts and ΔTc parameters. The blends resulting from the two bitumens displayed a similar evolu-tion of behavior. This outcome suggests that these tests cannot discriminate the origin of the re-juvenation phenomenon since they only highlight the softening effect of the recycling agent and not its impact at the molecular level, i.e. on asphaltene and maltene compounds.