Rheological evaluation of bitumen containing different ultraviolet absorbers

The dynamic rheological characteristics of bitumen with two ultraviolet absorbers (UVAs) were investigated by the dynamic shear rheometer test. To evaluate the effect of UVAs on the viscoelastic response of bitumen, the temperature and frequency dependence of the dynamic viscoelastic properties were compared. The low-temperature fatigue resistance and high-temperature rutting resistance of the modified bitumens were evaluated to predict the road performance. The results indicate that the bitumen containing UVAs follows a thermorheologically simple linear viscoelastic behavior since the UVAs can be considered as fraction of aromatics in bitumen and possess no complicated influence on the rheological properties of bitumen. The viscous component of bitumen is increased and the viscous response is prolonged by the UVAs. The UVA plays as a softener and endues bitumen with more favorable low-temperature performance, such as the improved low-temperature fatigue resistance.