Effect of oxidation kinetic aging on the adhesion behaviour of asphalt-aggregate interfaces from molecular view

ABSTRACT

Asphalt oxidation kinetic aging effect on the adhesion behavior of asphalt-aggregate interfaces at atomistic scale was investigated in this study. The asphalts were aged at different aging durations. The sulfoxide and carbonyl functional group content as well as SARA fractions of the asphalts at different aging times were studied through the tests of Fourier Transform Infrared Spectroscopy (FTIR) and Saturate, Aromatic, Resin and Asphaltene (SARA) fractions. Asphalt molecular models of virgin, rapid-rate aged, slow-rate aged and full-aged were established based on SARA fractions and FTIR results, to construct asphalt quartz and asphalt-calcite interface systems at different aging stages. The simulation results showed that the nanostructure of asphalt is influenced by the aggregate type and asphalt oxidative aging. The growth rates of adhesion energy of asphalt-quartz and asphalt-calcite systems increase rapidly first and then slowly with aging time, but the growth rates are different. Meanwhile, the Van der Waals energy is the major energy source of adhesion energy, and the contribution of van der Waals and electrostatic energy to adhesion energy is different. The aging of asphaltene and resin promotes the adhesion ability to quartz or calcite, while the aging of aromatic components is not conducive and the saturate has almost no effect.

KEYWORDS:

• Adhesion energy
• oxidation kinetic aging
• asphalt-aggregate interfaces
• molecular
• four components

Acknowledgments

The authors gratefully acknowledge the financial support from the National Natural Science Foundation of China (No. 52308461), Application Basic Research Project of Shanxi Province (No. 202203021211128), Shanxi Scholarship Council of China (No. 2022-066), the Science and Technology Project of Shanxi Provincial Department of Transportation (No. 2022-02-01, 2020-1-6), the Science and Technology Project of Shanxi Communications Holding Group Co., Ltd. (2022-JKKJ-18).

Disclosure statement

No potential conflict of interest was reported by the author(s).