Rheological modelling of asphalt materials properties at low temperatures: from time domain to frequency domain

Abstract

The rheological model, Huet model, which is composed of one spring and two power function elements, has two expressions: one in time domain, which is used for creep compliance, and one in the frequency domain, which is associated with complex modulus. Previous research efforts showed that the Huet model provides a very good fitting of experimental results obtained from creep and complex modulus tests on asphalt materials. However, the potential use of this model as an inter-conversion tool between the data obtained in the time domain and those in the frequency domain, and vice versa, was never previously evaluated. In this paper, the possibility of using the Huet model for predicting the complex modulus of asphalt binders and asphalt mixtures from the experimental data obtained from creep tests, performed with the bending beam rheometer at low temperatures, was investigated. The predictions obtained with the Huet model were experimentally verified by a set of complex modulus tests performed on 2 asphalt binders and 20 asphalt mixtures with the dynamic shear rheometer. The good agreement between the predicted and the measured complex modulus of asphalt binders suggested that the Huet model can be used for inter-converting data obtained in time and frequency domains. This was not verified in the case of the asphalt mixtures complex modulus data due to experimental limitations.

Keywords:

• bending beam rheometer
• dynamic shear rheometer
• Huet model
• time domain
• frequency domain
• inter-conversion

Acknowledgements

The authors gratefully acknowledge the Minnesota Department of Transportation for providing the materials used in this study and Mugurel I. Turos for his technical support during the experimental phase.