In order to make a deep research on the high-temperature permanent deformation performance ofasphalt mixture from a microscopic perspective considering the discontinuous feature of asphaltmixture, the virtual rutting test of asphalt mixture was developed using discrete element softwarePFC2D. According to probability theory, the conversion of the three-dimensional (3D) volumetricaggregate gradation to two-dimensional (2D) quantity gradation was developed. A generationprogram taking into account the irregular shape of aggregate was developed using Monte Carlomethod, based on which the 2D digital specimen was generated. The virtual rutting test wasdeveloped including the development of discrete element (DE) model of asphalt mixture, therepresentation of micromechanical behaviors within asphalt mixture, the determination ofmicroscale model parameters and the way of loading. In addition, An approach was presented onthe basis of the time-temperature superposition (TTS) principle to reduce the computation time ofvirtual rutting test. The formation of rutting, as well as the compaction and shear flow of asphaltmixture within loading area in virtual rutting test were analyzed. The simulation results werecompared with the experimental measurements. The results show that: 1) the approach based onthe TTS principle in DE viscoelastic model can significantly reduce the computation time; 2) thedeformation law of asphalt mixture in virtual rutting test was similar to the experimentalmeasurements, and the deformation and dynamic stability of virtual rutting test is a little greaterthan the experimental measurements; 3) the 2D virtual rutting test was able to predict thehigh-temperature permanent deformation performance of asphalt mixture.
展开▼
