Linear elastic dynamic fracture mechanics are adopted to analyze the working characters of the semi-rigid asphalt pavement with the reflective cracking . it is successful to simulate the crack expansion process based on elastic damage theory, at the same time the fatigue life is forecast . the research findings are valuable for the pavement engineering practice on the soft clay ground 本文分析路表变温对软土地基上半刚性路面结构体的作用时,考虑了路表降温导致沥青混凝土回弹模量的非均匀性,采用线弹性动断裂力学分析软土地基上含反射裂缝半刚性路面结构体的工作性状。