Investigation of asphalt mixture permanent deformation based on three-dimensional discrete element method

Abstract

The permanent deformation (especially rutting) is one of the most common failure of asphalt pavement, which seriously undermines the quality of highway service and is prone to induce cracks and other damage. Firstly, based on the laboratory Hamburg wheel tracking test, the AC-13 asphalt mixture virtual model was constructed through the particle flow code (PFC) of the three-dimensional discrete element method (3D DEM). Then, the virtual Hamburg wheel tracking test was performed to analyze at a mesoscopic level the deformation mechanism of the aggregate skeleton during the loading test, and the effects of temperature and pressure on the anti-deformation performance of asphalt mixture. The results demonstrated that the discrete element model can accurately simulate the rutting test of asphalt mixture, and the final relative error was below 10% in general. In addition, during the virtual Hamburg rutting test, the displacement of the aggregate in the Z-axis and X-axis directions increased with the growing numbers of loading, and there was a certain reciprocal movement of aggregate in the Y-axis direction. Moreover, the aggregate still maintained a high level of displacement at a certain depth from top to down inside the virtual specimen, indicating that the small depth of the asphalt pavement from the top to the bottom was the peak area where the structure suffered from shear.