The Study Of Rutting Lateral Hump Of Asphalt Concrete Pavement

Rutting is a major distress found in high-grade asphalt pavements.The generation of the rutting is mainly due to shear deformation of asphalt mixture, which caused depression at wheel track position,and occurred lateral hump at each side. This article scanned the transverse profile of rutting test and ring road experiment, combined with finite element analysis,studied the lateral hump of rutting deeply.In order to obtain more obvious lateral hump deformation to analysis the lateral hump deformation change rule with depth, and the load, load times,this article scanning transverse profile under different pressure, different temperatures and different times. And then the rut samples were cutted to analysis the flow pattern of material.The results showed that the hump coefficient defined by area ratio were better than the hump coefficient defined by height ratio.The hump coefficient getted larger with the temperature and load raised.The area raised speed at 70℃was larger than what at 60℃,which was 3.56 times at 0.7MPa, 3.09 times at 0.9MPa, 3.29 times at 1.1MPa. The fine aggregate account the most particial in the flow material,while the coarse aggregate moved in vertical direction.Large ring road test is the full-scale test of engineering between laboratory test and field entity, the test results had stronger significance to the actual engineering.So this paper studied the hump deformation regularity and the flow regularity of material in ring road test. the hump area and depression area showed a linear growth. The hump coefficient became stable and not changed significantly when the load times reached a certain number. The hump coefficient defined by area ratio were better than the hump coefficient defined by height ratio.This paper analysed the shear stress along the depth direction of rutting track under different pressures using ANSYS,the shear stress getted larger with the load became larger and the biggest shear stress occurred at 1.5cm.This paper also analysed the shear stress along the depth direction in different structures in ring road test,which found that different structures had not significant effects on the shear stress distribution in ring test.