The effects of chemical composition on asphalt microstructure and their association to pavement performance

Abstract

The primary objective of this paper was to investigate the impact of asphalt chemical composition on the microstructure and performance characteristics of asphalt binder. The methods implemented in this study include adsorption–desorption chromatography analysis and a range of atomic force microscopy (AFM) and chemical force microscopy techniques. It was revealed through the study that certain asphalt chemical parameters have a consistent and measureable effect on the asphalt microstructure that is observed with AFM. Particular microstructures that emerged via chemical doping were then discovered to have unique chemical polarity, which explicitly impact durability and performance of asphalt. In fact, a surprising correlation was found between the saturates chemical parameter and the effects of oxidative aging on asphalt behaviour. The findings from this research directly contribute to the improvement of modelling capability while also creating new prospects for enhancing the performance characteristics and durability of asphalt binder.

Keywords::

• asphalt
• chemical composition
• atomic force microscopy
• AFM
• chemical force microscopy

Acknowledgements

This work was funded by the Federal Highway Administration (FHWA) as part of the Asphalt Research Consortium (ARC). The authors would also like to acknowledge the National Science Foundation (NSF) [grant number CMMI-1053925] for partially funding this study and Mike Harnsberger from the Western Research Institute (WRI) for providing SARA samples.