Study On The Structure Of Composite Base Of Asphalt Pavement Resisting Reflection Cracking

It's a big problem that the craks reflected on our semi-rigid asphalt pavement, which causes the early destruction of the pavement. Recently,composite base of pavement is widely used in China,to reduce the reflective cracks of semi-rigid base and improve the life of the road service. Since that's no theory for the design of crack resistance at present, the current study on the material chosing and the thickness determineing always depeded on experience,with no reasonable quantitative calculation. And this makes the application of the structure more subjective, so the applications of composite base need a set of asphalt pavement for the control of reflection cracks in the design approach to improve the design process more scientific.This paper building a cracking prediction model compositing desiccation and temperature on base of the practice of Qing Hong expressway in Hebei province. And using which anlisys the laws of the cracking prediction of bare or pavement covered semi-rigid base,then a cracking rating standard was built for semi-rigid base. compared the performance of materials used in flexible pavement and its ability of crack resistance, a comprehensive eveluation method is built composit more index about flexible materials crack resisting effect.A model is bulit in this paper to prediction the fatigue life of anti-cracking,and the crack resisting functional zone is been definited on the base of anlsys the law of cracking propagation,and the anti-cracking fatigue life is first bulit for crack resisting functional zone.And also the reflective cracking process control method for 8 years life of is put forward.Composite Base Asphalt Pavement Climate Division is established in this paper combined the climatic factors effect of composite asphalt pavement, and so put forward the corresponding recommended structure. Based on the above contents, a design method for composite base asphalt pavement is first put forward based on control of reflection cracks.For the purpose of verification the theory of this paper and to explore the construction technology,10 test sections with the length of 4960 m were paving on field in Hebei province. The results gained from field proof the theory and model of in this paper as good practical.