Abstract:The deflection basins of roads under moving load imply the distress information of subgrade and pavement.Therefore,how to use the information of deflection basins under moving load to rapidly test road distresses non-destructively has received much attention.In this paper,the finite element model of semi-rigid base asphalt pavement was established.By setting different types and degrees of finite element distress models,the continuous changes of surface deflection basins under moving load were analyzed.The results show that when the load moves to the distress area,the center deflection value of surface deflection basins in each distress model will become larger.When transverse cracks appear in the pavement structure layer,the shape of the deflection basins will change.The through transverse cracks have the most obvious influence on the shape of the deflection basins.The influence of the locally loose base and subbase on the shape of the deflection basins is more obvious than that of the loose surface.When a void appears at the top of the subgrade,the shape of the deflection basins is almost unchanged.Subgrade mud pumping will seriously affect the shape and size of surface deflection basins.