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K. Hofer, J. Mirwald, B. Hofko:
"Impact of Temperature and Atmosphere on Bitumen Ageing";
Talk: IRF World Meeting & Exhibition, Dubai; 2021-11-07 - 2021-11-10.

The aging phenomenon of bitumen is one of the main causes for road pavement failure, which is why it is important to understand and simulate bitumen aging realistically in the laboratory. Therefore, the "Viennese Binder Aging Method" (VBA) for long-term aging of bitumen has been developed, where reactive oxygen species (ROS) are used to generate a similar aging atmosphere to the field. To minimize the possibility of excessive temperature altering the aging mechanism and changing the molecular interactions in the material it is crucial to carefully choose the temperature at which the aging experiments are performed. In this study, two different bitumens
(70/100 pen and 160/220 pen) are exposed to different temperatures (60-100°C) and atmospheres (pressured air, nitrogen, oxygen) for various periods of time
(3 and 6 days). The bitumens are then analyzed by Fourier-Transformation Infrared (FTIR) spectroscopy and the dynamic shear rheometer (DSR) to investigate the change in mechanical properties and the respective chemical composition of the material. Thus, we aim to obtain knowledge about the effects that temperature in combination with different atmospheres has on bitumen properties and whether these effects vary depending on the bitumen source. Furthermore, we hope to reach an aging temperature for the VBA that reflects field aging conditions and provides high enough reaction rates for reasonable ageing durations, but does not induce grave changes in the reaction mechanism found in the field.