High temperature rheological characteristics of activated crumb rubber modified asphalts

Crumb rubber modified asphalt has gained growing interest as environmental friendly binder in last few decades. The objective of this study was to investigate a new treatment method of crumb rubber impact on the high temperature rheological performances of modified binders produced with two base binders and six crumb rubbers at virgin and the RTFO states. Firstly, FTIR test was conducted to determine the functional groups in all rubbers. For all of the binders, the viscosity value, failure temperature, rutting resistance factor, storage modulus and phase angle were obtained by the rotational viscometer and dynamic shear rheometer at different temperatures and aging states. FTIR curves showed that S=O appeared after rubber surface treatment. The results illustrated that the high temperature rheological properties of all rubberized binders tested in this research project were improved regardless of binder and rubber sources as well as rubber type. In addition, the treatment is only recommended to be applied on the typical rubber to get promotions towards rheological performances at high temperatures. On the other hand, short term aging resulted in positive effect on these performances. (C) 2018 Elsevier Ltd. All rights reserved.