AC-13C沥青混合料劈裂疲劳损伤试验二维数值模拟

Two-dimensional numerical simulation of splitting fatigue damage test of AC-13C asphalt mixture

沥青混合料受非均匀性细观结构影响,其刚、强度力学特性易发生变化,为分析受细观结构影响的沥青混合料力学疲劳损伤特性,本研究从细观尺度出发,结合室内劈裂试验结果,利用有限元软件建立二维数值模型分析沥青混合料的力学与疲劳损伤特性。结果表明:在沥青混合料疲劳损伤过程中,粗集料尖角附近应力集中现象明显,疲劳损伤往往先在粗集料尖角处发生;AC-13C数值模型应充分考虑2.36 mm以上的粗集料,并在细观尺度上说明2.36 mm作为AC-13C粗细集料分界线的可行性。

In order to analyze the mechanical fatigue damage characteristics of asphalt mixtures affected by meso-structure, a two-dimensional numerical model was established using finite element software to analyze the mechanical and fatigue damage characteristics of asphalt mixtures based on meso-scale and indoor splitting test results. The results show that in the fatigue damage process of asphalt mixture, the stress concentration near the sharp corner of coarse aggregate is obvious, and fatigue damage often first occurs at the sharp corner of coarse aggregate. AC-13 C numerical model should fully consider the coarse aggregate above 2.36 mm, and illustrate the feasibility of 2.36 mm as the demarcation line of AC-13 C coarse aggregate on the meso-scale.