Influence of selected reactive oxygen species on the long-term aging of bitumen

Abstract

The aging of bitumen is a major contributor to the failure of asphalt pavements. Realistic and accurate laboratory aging methods can predict bitumen durability and guarantee the use of high-quality components in asphalt pavement. However, current standardized aging methods do not incorporate atmospheric parameters, besides elevated temperatures and molecular oxygen. Crucial chemical components like reactive oxygen species (ROS), e.g. nitrogen oxides (NOx) or ozone (O3), are completely neglected. This study focusses particularly on the reactivity of individual ROS, such as nitrogen monoxide (NO), nitrogen dioxide (NO2) and O3, in regards to the long-term aging (LTA) of three unmodified bitumen. For LTA an adapted version of the Viennese Binder Aging method was used and the aged bitumen samples were analyzed with the dynamic shear rheometer and Fourier-Transform-Infrared spectroscopy, respectively. The results show that NO as a single component does not induce significant aging, whereas NO2 leads to severe bitumen deterioration, which is even more accelerated when a second oxygen source is present. In comparison, the reactivity of O3 is rather mild and it did not cause additional aging for two of the investigated binders. This study provides evidence, that ROS play a crucial role in bitumen aging and should thus not be neglected when addressing realistic aging conditions in the laboratory.

Microevolution of Polymer–Bitumen Phase Interaction in High-Viscosity Modified Bitumen during the Aging of Reactive Oxygen Species

“…This suggests that the aging impact of ROS increases the area of bee structures in BB. According to the study by Hofer et al, the NO 2 in ROS decreases the activation energy of the reaction between O 2 and bitumen, hence accelerating the bitumen oxidation reaction. Also, the NO 2 reacts with O 2 to form higher elevated oxygen states, which have greater energy and also promote oxidation of bitumen.…”

“…16 ROS appears to be more reactive than oxygen, making it easier to combine with the reactive radicals of the binder, hence accelerating the aging of the binder. 17 Therefore, if we want to mimic the realistic field aging of PA pavements, we cannot overlook the role of ROS. However, fewer studies have examined the aging of PA pavements and HVMB due to the ROS at the road surface.…”

“… , As a key aging factor, the reactive oxygen species (ROS) have attracted the attention of some scholars since 2020. ,, PA pavements have well-developed void structures and are in complete atmospheric contact . ROS appears to be more reactive than oxygen, making it easier to combine with the reactive radicals of the binder, hence accelerating the aging of the binder . Therefore, if we want to mimic the realistic field aging of PA pavements, we cannot overlook the role of ROS.…”

Analysis and Prediction Model of Styrene-Butadiene-Styrene-Modified Asphalt Aging by Infrared Spectroscopy

“…Numerous studies on asphalt aging degree and prediction models have evaluated the aging degree of asphalt by the viscosity index, ductility ratio, penetration ratio, component ratio, toughness index, visible light, reactive oxygen species, and so forth (6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17). Liang et al (18) simulated field-and laboratory-aging points to a generic framework for studying the effect of aging on asphalt binders, but a more suitable dynamic shear rheometer (DSR) shape is needed for further studies.…”