Identification of aging fingerprint of base asphalt by ATR-FTIR combined with chemometrics

In this work, attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) combined with chemometric analysis was used to classify and characterise aged asphalt. The full spectra of asphalt samples with 5 types at 6 aging states (30 samples) were determined using ATR-FTIR and the data matrix of the full spectra was analysed chemometrically. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) outcomes demonstrate that the asphalts of five oil sources are divided into three major categories. The samples of asphalt prior to and following aging with comparable oil sources are still grouped into one category. With up to 100% accuracy, one can discriminate between the asphalt samples from these three oil sources using Fisher's discriminant function based on PCA and HCA cluster analysis.This indicates that the aging characteristics of asphalt depend on the oil source, and the "genetic framework" of asphalt will not change with aging.