Modeling of Asphalt Aging Based on Short-Term Aging Temperature and Time of Normal Asphalt Mixture for Quantifying Binder Aging

Abstract

The binder in hot-mix asphalt (HMA) is aged (oxidized) in a short-time period during haul-and-queue in the field. Since the oxidative aging of asphalt is a complex chemical process, it is difficult to define the asphalt aging as a function of limited variables. When comparing the same types of asphalt mixes, however, the mix temperature (T) and time (t) kept at the T will be the primary source of variation affecting aging levels of the binder in the mix. Since the binder aging level is not easy to estimate without measuring a physical property, this study concentrated on developing an aging quantity (AQ) model for estimating aging levels of the binder in the mix based on T and t. The loose asphalt mixes were artificially short-term aged at various Ts for different t; 130, 160, and 180 °C for 1, 2, 4, and 8 h. The absolute viscosity (AV) values, which represent aging levels of the recovered binder after each short-term aging (SA) of normal dense-graded mix, were used for regression with AQ values computed by the AQ model. The best-fit AQ model was selected by trial-and-error regression iterations between measured AV and computed AQ. The AQ was then used to estimate AV (EAV) of the aged asphalts in various normal asphalt mixes. It was found that the AQ was useful for estimating AV of the binder in the SA-treated mix, and the EAV by AQ showed an excellent correlation with the measured AV with R2 > 0.99. Therefore, it was possible to conclude that the AQ could be used to predict aging level of various short-term-aged normal asphalt mixes if the materials sources were limited.

Effects of Different Natural Factors on Rheological Properties of SBS Modified Asphalt

“…Affected by external factors such as high temperature, sunshine, rain and oxygen, it is easy to cause cracking, loose, rutting and other diseases, and its service life is much lower than the design life [1,2]. However, the asphalt-aging factors considered are still concentrated on thermal oxygen, UV, water and other factors, which are relatively single, and most of them also use laboratory simulation methods, which cannot reflect the service conditions of asphalt pavement in the real environment [3,4]. The asphalt samples at different aging stages are mainly obtained through accelerated simulation in the laboratory.…”

An Active Anti-Aging Technology for Asphalt Mixture

“…Oxygen, sunlight, temperature, moisture, and other factors can cause asphalt aging during its service as road pavement [1][2][3][4][5], which can severely degrade the performance of the asphalt pavement and greatly shorten its service life. In such case, special treatment measures are required to suppress the aging of asphalt pavement, so developing anti-aging materials is very meaningful for improving the performance of asphalt pavement and prolonging its service life [6][7][8][9][10].…”