The Study On The Mechanical Properties Of Interface Between Semi-rigid Base And Asphalt Pavement

The asphalt pavement based on semi-rigid type base has got extensive application in our country's road construction because of its advantages, such as high intensity, low cost, good performance of plate and adapting to channeling traffic. However, the properties of the materials which combine semi-rigid base and asphalt layers vary so widely, both structure interface is not properly bonded that easily lead to the asphalt pavement early damage, such as the sliding of asphalt layers, arching and early fatigue cracking;How to restrain reflective crac from the semi-rigid base developing asphalt surface at interface.Therefore, it is necessary to carrying on the systematic research of main problems of the interface which lies between the semi-rigid base and asphalt layers, Maintaining a good interface characteristics is a crucial role to guarantee the normal life of the asphalt pavement.Based on the trial-section of Xinhe highway, combined with series of indoor tests, tests on spot and a great deal of theoretical analysis, the paper studies on the following aspects: (1) The researches about polluted interface are carried on through the direct shear and pull test, drawing the law of the soil, oil pollution on the semi-rigid base layer .(2) Based on multi-layered flexible system, analyzing stress in the pavement structure under the conditions of different polluted interfaces, So high-qualified interface has an very important role to ensure that the asphalt well and has a very good road performance.(3) Analyzing main factors of the resistance to reflection crack in seal coat, selecting the good material of seal coat, and then compare with the different strength of elastic composite layers, combined the bending and shear fatigue tests, the fiberglass grille flexibility composite layers is the strongest. (4)Depending on fracture mechanics finite element model, analyzing the principle of flexible composite layers to delay the development of reflection cracks, good elastic deformation, low modulus and tensile modulus of elasticity of which is good road performance.(5) Paved trial-section roads verify that the elastic composite layers has a good crack resistance.