Frequency Dependency and Constitutive Model of Dynamical Mechanical Properties of Cement Asphalt Binders

Abstract

Using the dynamic mechanical thermal analysis (DMTA) method, the frequency dependence of dynamic mechanical properties of cement asphalt (CA) binders were examined within the testing frequency range between 0.1 and 100 Hz in this study. Based on the time-temperature superposition (TTS) principle, the master curves of storage modulus (E′), loss modulus (E″), and loss factor (tanδ) of CA binders within a wide frequency range from 1 × 10−5 to 1 × 1010 Hz were obtained. The results showed that the E′, E″, and tanδ of CA binders were highly sensitive to the frequency due to the incorporation of asphalt. The value of E′ rose as the frequency increased, whereas E″ and tanδ showed different trends as the frequency increased. Storage modulus rising factor ΔE′ and peak value of loss factor tanδmax could be used to characterized the frequency dependence of dynamic mechanical properties. A simple solid model with fractional derivation was established to characterize the dynamic viscoelastic behavior of CA binders and was in excellent agreement with experiment data over both testing and a wide range of frequency. Correlations were observed between model parameters and asphalt content of CA binders. Our results contribute to the current field by providing the evidence for the dynamic mechanical properties estimation of CA mortar under various loading frequency.