Numerical Analysis Of Viscoelastic And Fracture Behavior Of Asphalt Concrete Based On Internal Microstructure

Asphalt mixture contains aggregate, asphalt mastic and air voids. Not only the contents of these constituents, but also the distribution of these constituents both influence the mechanical behavior of the asphalt concrete. Thus, to introduce the microstructure of asphalt concrete to study the various mechanical features has the positive meaning.This paper analyze the character of the internal microstructure of asphalt concrete based on image processing technology, extract the partition of coarse aggrate in asphalt microstructure to present the geometrical feature of internal structure, and extract the information of the coarse aggregate, including the boundaries and position information, so that can construct a geometrical model for numerical analysis. So, base on the geometrical model, assign different material property to aggregate and asphalt mastic, it analyzes the viscoelastic response of asphalt concrete in split test, including the distribution regularity of Mises stress, creep strain, total displacement and horizontal displacement. and analyzes the crack evolution in asphalt mastic and the influences of aggregate in the test. The results successfully reveal the Distribution Regularities of stess, strain and displacement in the virtual spit test of asphalt mixture, the relation between creep strain and the distance in coares aggregate, the crack propagation in asphalt mastic and the relation between the crack propagation between the coarse distributions.