Evaluation of Different Procedures and Models for the Construction of Dynamic Modulus Master Curves of Asphalt Mixtures

Abstract

The dynamic modulus |E*| is the primary input material property of asphalt
mixtures for the asphalt pavement design procedures based on mechanistic principles. Among
other factors, this dynamic modulus is a function of temperature and loading frequency. In
order to model the effects of these factors, the dynamic modulus of the asphalt mixture is
described using a master curve constructed at a given reference temperature on the basis of
the principle of frequency-temperature superposition for thermo-rheologically simple
materials. The amount of shifting at each temperature is given by a shift factor that describes
the temperature dependency of the material. Different methods and mathematical functions
have been proposed to model these shift factors and the resulting dynamic modulus master
curve. The objective of this paper is to evaluate these various methods and mathematical
equations that can be satisfactorily used for modelling the dynamic modulus |E*| master
curves, as a function of frequency at a reference temperature for six different asphalt mixtures
used in Argentina. The methodology for evaluating these models was based on using the same
laboratory test data and comparing the resulting curves through correlation analysis. The
experimental results and a description of the considered procedures and models used to
develop the master curves are presented followed by a comparative analysis and a synthesis of
the obtained findings.