Bitumen is adhesive that originates from crude oil and is temperature dependent material including hydrocarbon molecules. Paraffinic crude oils may provide bitumen of good quality or yield bitumen which is not suitable for pavement performance. Wax in bitumen has been referred to as petroleum wax and is obtained from refining of paraffinic crude oils. The effects of wax on bitumen properties depend on the following factors; the source, chemical composition and rheology of the bitumen as well as the content, type, composition and crystallization of the wax. Although high wax contents have been considered as a negative effect on the quality of the bitumen, there is no common agreement among the scientists regarding the effect on bitumen rheology and asphalt performance. The scope of this study is to evaluate the rheological properties of waxy bitumens obtained from different sources. Following the determination of wax contents by DSC (Differential Scanning Calorimetry) and EN 12606-1, waxy bitumens properties were evaluated using dynamic shear rheometer (DSR) and various conventional methods such as softening point, penetration, viscosity, and ductility. The high temperature performance levels of bitumen were also determined according to Superpave system by dynamic shear rheometer (DSR) test on samples before and after aging processes. Besides, bending beam rheometer (BBR) test has been conducted to investigate the lower critical temperatures of bitumens. Rutting performance of bitumens has also been evaluated using Zero Shear Viscosity (ZSV) and Multiple Stress Creep Recovery (MSCR) tests performed in creep mode.
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