Development and Implementation of a Finite Element Model for Asphalt Mixture to Predict Compressive Complex Moduli at Low and Intermediate Temperatures

Many researchers recognized that micromechanical models have tremendous potential in the field of asphalt technology, for reducing or eliminating costly tests to characterize asphalt-aggregate mixtures for the design and control of flexible pavement structures and materials. The objective of this study is to develop micromechanical based finite element (FE) model to capture the microstructure of asphalt mixture and to predict mixture properties. In this approach, various material phases (aggregates and mastic) are modeled with a number of fine finite elements. Aggregate geometry, shape, orientation, and gradation are considered in the modeling. Furthermore, high-resolution images are used to study the microstructure of asphalt mixture and to prepare geometry input for the FE model. In addition, the complex modulus (E*) of the sand mastic (asphalt plus fine aggregate) are measured by an experimental program and used to compare the prediction of FE model. The E* of the asphalt mixture are measured and used to compare the prediction of FE model. The developed FE approach has the ability to predict asphalt mixture complex moduli in compression across a range of loading frequencies at low and intermediate temperatures (–20, –10, and 0°C).