Simulation Analysis of Reflection Crack Propagation Path of Asphalt Overlay Under Coupling Load

At present, the widely used scheme in the cement concrete pavement reconstruction and extension project is to add asphalt surface layer. It is urgent to elaborate the spreading principle of reflection crack. In this paper, the typical asphalt overlay structure of an urban road reconstruction and expansion project in Nanning, Guangxi is taken as an example. Combined with the theory of fracture mechanics, the plane strain model is established by ABAQUS software to analyze the changes of stress, strain field and expansion path of each reflecting crack propagation step under coupling load. The results show that the stress and strain field of the crack tip increase with the upward expansion of the reflected crack, and develop rapidly in the late expansion period. The crack propagation Angle decreases with the crack propagation. The expansion path tends to extend upward on the side without load, and the path gradually deviates from the side under load with the expansion of cracks, and the extension length also increases gradually.