Development of 3‐D finite element model for flexible pavements

Abstract This paper presents the development of a three‐dimensional finite element model for flexible pavements. The procedures of building a model and performing static analysis with the ABAQUS package are introduced. The element shapes and the size of the finite element model were studied to improve analysis efficiency. The model should at least consist of finite elements up to three times the loading diameter if centered at the loading position. Infinite elements should be used beyond the boundary of finite elements. The accuracy was justified with Boussnisq solutions for semiinfinite elastic solids. The surface layer was modeled with creep test data of asphalt concrete. Viscoelastic behavior was observed for the pavement model under wheel loading. The model was also validated by comparing computed results and field test data. Further calibrations of the model are underway by comparison with laboratory test results. The application of the model is introduced with an example of placing a geogrid‐reinforced asphalt concrete overlay on rigid pavement. Significant reduction of tensile strains at the bottom of the asphalt concrete was found with geogrid reinforcement.