Image-Based Modeling of the Dynamic Complex Modulus Test for Asphalt Concrete

Due to the limitations of the elastic continuum theory, pavement engineers have recently paid considerable attention to the use of advanced modeling techniques for simulating the realistic behavior of asphalt mixtures. The objective of this study is to develop a three-dimensional (3D), heterogeneous model to describe the response of asphalt mixtures in the dynamic complex modulus test using an x-ray computed tomography (CT) image-based FE modeling approach. Experimental testing results for two Superpave mixtures including one conventional hot-mix asphalt (HMA) and one warm-mix asphalt (WMA) mix were used to validate and to calibrate the developed FE models. Adequate agreement between laboratory-measured and model-predicted dynamic modulus test results was achieved. Results of the developed FE models at different temperatures indicated that most of the deformations during the dynamic modulus test are derived from the mastic. In addition, asphalt mastic had more influence than the aggregates on the results of the dynamic complex modulus test.