本文通过裂缝梁的纯弯曲实验，研究了沥青混合料的延迟开裂性能，测得在一定加载速度，不同试验温度条件下沥青混合料的断裂韧性，并观测不同荷载水平和不同温度状况下的裂缝扩展规律。研究结果表明，沥青混合料具有粘弹性流体性态；裂缝在沥青混合料中的扩展表现出明显的粘弹塑性断裂特征，并且证实，在研究沥青混合料的断裂参数时，简单热流变材料的本构模型依然适用。 In this paper, through the pure bending experiment of cracked beam, the delayed cracking performance of asphalt mixture was studied, the fracture toughness of asphalt mixture under certain loading speed and different test temperature was measured, and the cracks under different load levels and different temperature conditions were observed. Expand the law. The results show that the asphalt mixture has a viscoelastic fluid behavior; the expansion of cracks in the asphalt mixture shows obvious viscoelastic-plastic fracture characteristics, and it is confirmed that in the study of the fracture parameters of the asphalt mixture, the simple thermal rheological material The constitutive model still applies.