Cracking mechanism of TopDown cracking in asphalt pavements based on fracture mechanics
1. Key Laboratory for Special Area Highway Engineering of Ministry of Education, Chang′an University, Xi′an, Shaanxi 710064, China; 2. Kevin Shandong Science and Technology Career Academy, Jinan, Shandong 250200, China
Abstract：Based on the threedimensional finite element analysis in ABAQUS software, with considerations of the modulus gradient of asphalt pavement by aging and temperature gradient, the suddenly cooled down temperature and the concentration of tire edge stress, three seasons of spring, summer and winter and three conditions of slowing cool down before aging, slowing cool down after aging and sudden cooling down after aging were selected to establish nine finite element asphalt pavement models with cracks. The stress intensity factors of TopDown cracking(TDC) under different working conditions were analyzed. Combining the theory of the maximum circumferential tensile stress, the cracking mechanism and the prediction method of TDC were given. The results show that the stress intensity factors of shear mode are the main cause for the propagation of cracks under the conditions of slowing cool down before aging and slowing cool down after aging. The stress intensity factors of opening mode are the main cause for the propagation of cracks under the condition of sudden cooling down after aging.
2017, Vol. 38 
