Modelling the rheological properties of bituminous binder using a mechanical model

Abstract

Modelling is a very useful way to fit or describe the linear viscoelastic (LVE) properties of bituminous binders, which cannot be done via laboratory work. This study investigates the applicability of LVE rheological models called the 2S2P1D (combinations of two springs, two parabolic elements and one dashpot) model on different types of bituminous binders. The rheological data of unaged and aged unmodified bitumens, bitumen-filler mastics and polymer-modified bitumens were measured using a dynamic shear rheometer (DSR) in the LVE region. It was found that this model with seven parameters fits the measurements reasonably well over a wide range of temperatures and frequencies. The correlation between measured and descriptive data was evaluated by means of the goodness-of-fit statistics method. Except for the unaged polymer-modified bitumens, the other samples show good agreement between the measured and descriptive complex modulus and phase angle data