| In the paper,random aggregate generation and packing algorithm is utilized to create two-dimensional heterogeneous models of asphalt mixture,and based on that technology the extended finite element method is used for calculation and analysis on the model.The main achievements in this paper are shown as follows:(1)The three-point bending tests for single-edged notch specimens containing different orientations are performed, to explore the relationship and difference between them. The experimental results show that notch location has important effects on load-displacement curve and crack propagation path.(2)The random aggregate generation and packing algorithm is developed to create a two-dimensional heterogeneous model of asphalt mixture. By comparing numerical simulation experimental results, the limitation and feasibility of the model and the method of extended finite element are verified. At the same time, the influence of aggregate distribution on cracking behavior is deeply explored,in order to realize the extended finite element method in the application of heterogeneous materials.(3)A multiscale modeling frame combining macroscale and mesoscale is set up to achieve the balance between the computation efficiency and the accuracy. In this frame,the mesostructural models are created in some concerned local regions and only in the concerned local regions the extended finite element method is used.It is proved that the mutiscale modeling frame is feasible and reasonable by comparing the numerical simulation results with the experimental results. |
