INFLUENCE AND MECHANISM OF ULTRAVIOLET AGING ON BITUMEN PERFORMANCE

Ultraviolet (UV) and thermal aging are two quite different types of aging. This study experimentally compares UV aging with thermal aging of several bituminous binders. Bitumen was evaluated with respect to its changes in physical and rheological properties. The results show that bitumen has different sensitivities to UV and thermal radiation. Penetration values, softening point and ductility of UV-aged bitumen are not the same as those in thermally aged bitumen. Rheological indices also reveal that UV aging and thermal aging have different influences on bitumen. The low-temperature property degraded remarkably due to UV aging. This paper also explains the mechanism of aging behaviour using infrared spectroscopy and chemical component investigation, and points out that aromatics and resins are the crucial chemical components for the anti-UV aging ability of bitumen. 1