Investigation of rheological properties of modified bituminous binders obtained from different elastomers before and after short-term aging

The bituminous pavement layers used in the flexible pavement of the road are the top layer that is directly exposed to the effects of traffic and the environment, and therefore must be quite robust in terms of mechanical properties. In order to resist the increasing traffic load and number of bituminous hot mix layers for a long time without deforming, the binder bitumen material commonly used in the mix is modified with the Styrene-Butadiene-Styrene (SBS) polymer additive. The high demand for SBS makes it difficult to supply when needed and therefore, the use of alternative additives is on the agenda. In this study, three different elastomers (701, 611 and SBS) were compared. In addition, the effect on the physical, chemical and rheological properties of the bituminous binder was also investigated. Modified bitumen was prepared by using SBS, 701 and 611 elastomers prepared under the specified conditions. Conventional (penetration, softening point, ductility and viscosity) and Superpave binder (dynamic shear rheometer, beam bending rheometer, short and long term aging) tests were performed on pure and modified binders. In addition, Fourier Transform Infrared Spectroscopy (FTIR) test was applied on aged modified binders. The applied test methods are aimed at determining the low and high temperature performance, aging resistance, machinability and flexibility properties of binders. As a result, when the conventional and Superpave binder test results of 5 different binders used in the study were examined, it was determined that these binders increased the performance of the pure binder. According to the results of the binder tests, the usability of 701 and 611 elastomers instead of SBS elastomers was determined. Especially, according to the results obtained from 611 elastomers, rutting performance was determined to be better than other elastomers