ABSTRACT
Almost all bitumen obtains from crude oil by refining process but only certain crude oils contain good quality bitumen for asphalt pavement. Naphthenic-base crude oils often give a large amount of bitumen that may be good quality, while paraffinic crude oils may give bitumen of good quality or yield bitumen not suitable for asphalt pavement. Wax in bitumen has been referred to as petroleum wax and is obtained from refining of paraffinic crude oils. In spite of the fact that 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 two different methods, various conventional methods were performed. 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. The intermediate temperatures performances levels of bitumen were also performed by DSR. Rutting performance of bitumens has been evaluated using Zero Shear Viscosity (ZSV) and Multiple Stress Creep Recovery (MSCR) tests.
