To understand in depth the behavioral characteristics of different asphalt pavements under traffic loads, the MLS66 accelerated loading facility was used to simulate actual vehicle running. The dynamic responses of semi-rigid pavement and inverted structured pavement in three directions were measured, and the strain responses at the bottom of the surface course and the bottom of the base course to the central load and eccentric load were studied respectively. The measurement showed that the value of the bending strain at the bottom of the base course of the semi-rigid structure was higher than that of the surface course. The inverted structure was more sensitive to the num-ber of loading cycles because the value of the tensile strain in the inverted structure was much higher than that in the semi-rigid structure. The maximum tension strain in the inverted structure appeared on the bottom surface in the longitudinal direction, and fatigue cracking first appeared in the horizontal direction. The strain responses of both structures'surface course show the viscoelastic characteristics of the asphalt mixtures. The strain measurements un-der various loads indicate that the tire-pavement contacting pressure should be the primary estimating parameter when the overloaded vehicles are considered. The study of the dynamic responses of the pavement through the use of MLS66 helps to gain an understanding of the damage mechanisms of the various asphalt pavements.%为深入了解交通荷载作用下不同沥青路面的行为特征，通过MLS66加速加载设备模拟实际车辆作用，实测了半刚性基层结构与倒装结构路面的3个方向动态响应，研究了正载与偏载时面层与基层底部的应变响应规律。实测应变显示：半刚性路面中基层底部拉应变大于面层。倒装结构面层底部弯拉应变大于半刚性路面，对荷载作用次数更加敏感。倒装结构中最大拉应变出现在面层底部纵向，疲劳开裂首先在横向出现。2种结构的面层应变响应均体现了沥青混合料的黏弹性特征。不同轴载下应变测值表明，考虑超载车辆对路面结构作用时，应选用接地压力作为参数进行计算。基于MLS66的路面结构动力响应研究，为理解不同路面结构的破坏现象提供了帮助。
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