Analysis of Asphalt Aging Behavior Evaluation Method Based on Infrared Spectrum

Abstract

In order to analysis under microscopic scale fast evaluating asphalt asphalt aging mechanism and aging degree, Fourier transform infrared spectroscopy were used respectively to solvent method and ATR method to transmission spectra analysis of matrix asphalt, secondly by ATR method of matrix asphalt tested functional characteristics before and after the RTFOT aging, qualitative and quantitative analysis of the functional groups. The results show that there is no difference between the infrared spectra of the solvent method and the ATR method. Some carbon and sulfur elements in asphalt are oxidized to form carbonyl C=O and sulfoxide S=O functional groups during the aging process, and the oxidation of sulfur element is the main one. The sulfoxide index (SI) and carbonyl index (CI) are well correlated with the penetration degree of asphalt, the correlation coefficient reaches 0.83 and 0.84, respectively. The aging of asphalt increases the sulfoxide index (SI) and carbonyl index (CI), and the asphalt becomes hard and the penetration degree decreases. Infrared spectroscopy can effectively evaluate the aging behavior and degree of asphalt, which provides a new method for rapid detection of aging asphalt.