Dynamic modulus and phase angle prediction of laboratory aged asphalt mixtures

Abstract

Performance of asphalt mixture is highly influenced by oxidative aging. A considerable amount of research has been dedicated to study the aging process of asphalt binder, while the effect of other contents of the mixture on aging characteristic, such as aggregates and additives, has been overlooked. This work investigates the effect of aging on dynamic modulus and phase angle by conducting dynamic modules test on asphalt mixtures aged at nine different levels in laboratory. Test results are used to determine the parameters of a kinetic-based aging model. The model is then incorporated into a set of regression models to predict dynamic modulus and phase angle master curve of the aged mixtures. The regression models are constructed based on the relation of sigmoidal coefficients of the master curves and shift-factor parameters with a normalized kinetic-based aging function. The proposed model is validated for a mixture aged at a predefined condition by comparing the predicted phase angle and dynamic modulus with lab measurements.