Viscoelastic material functions such as time-dependent relaxation modulus or creep compliance, and frequency-dependent complex modulus can be used to characterize the linear viscoelastic behavior of asphalt concrete in advanced modeling and pavement design. Among these, complex or dynamic modulus has been adopted in the new mechanistic-empirical (M-E) pavement design method. In this study, a procedure is documented to interconvert one material function from another. In essence, cylindrical AC specimens were tested for complex modulus as a function of loading frequency and temperature and hence, the time-temperature superposition principle was used to generate mastercurve. The complex modulus function is then converted to relaxation modulus and creep compliance by a numerical method. These converted material functions were then compared to the tested material functions. A good agreement was found between the measured and the converted material functions. The mastercurves were used to study aging in asphalt concrete sample. It is shown that various linear viscoelastic material functions of aged asphalt concrete sample vary significantly from those of unaged sample.
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