CHARACTERIZATION OF THE NONLINEAR BEHAVIOR OF FLEXIBLE ROAD PAVEMENTS

In this paper, the Asphalt Concrete is analyzed by finite element modeling in Abaqus. The nonlinear viscoelastic behavior of Asphalt Concrete is simulated in Finite Element Analysis (FEA). The X-Ray Computed Tomography scans of the laboratory specimen are converted to a 3D virtual model in image processing software (Simpleware Scan IP). The 3D model is used in FEA by applying boundary conditions and giving mechanical properties, considering the Asphalt Concrete as a viscoelastic material. The mechanical properties of the Asphalt Concrete were determined from the laboratory test performed on the same sample. Three different types of model were analyzed. The representative 3D meshed model and Abaqus meshed model were analyzed for recovery of stress under constant strain and compared. It was concluded that the analysis on a model without considering the actual geometry of the Asphalt Concrete, gives a similar pattern of results but differ by 18% than a laboratory test. The actual 3D geometry of Asphalt Concrete specimen can be obtained by converting 2D X-ray CT scans. It was also found that the nonlinear viscoelastic analysis on a 3D virtual model of Asphalt Concrete gives 96% similar results to the laboratory tests.