Dynamic mechanical response for bituminous mixtures in wide frequency range

Abstract

The rheological properties of bituminous mixtures at different test temperatures have been determined by means of a Dynamic Mechanical Analyzer (DMA) via frequency sweep with a relatively wide range between 0.02 Hz and 200 Hz. The measurements were carried out by controlled-strain mode in three-point bending beam test. Continuous spectra were obtained, covering four decades of the frequency scale for phase angle as well as storage and loss moduli with loading frequency. The storage and loss moduli are found to increase as loading frequency increases and temperature decreases. The variation of phase angle with frequency is complicated. Under low test temperature, the phase angle decreases with increasing frequency; under higher temperature, it shows a contrary trend. It is interesting that a peak phase angle appears for these bituminous mixtures in the intermediate temperatures. In addition, the DMA measurement can be used as an effective method to evaluate the viscoelastic properties of bituminous mixtures with fine aggregates.