The Stress Analysis For Surface Layer Of Cement Concrete Pavement With Function Layer

Cement concrete pavement is a widely used form of road, with high intensity, good stability, long life, low maintenance costs, such as repair many advantages.Now more and more attention are paying to this road. The imperfect contact between the cement concrete pavement and the base layer is one of the main reasons for the pavement surface damage.The functional layer of asphalt is undoubtedly set to solve this problem. The existing Specifications of Cement Pavement Design for Highway details the structure of cement concrete pavement design method,but did not consider the coordination of Structure design.This paper analysis described FEM(Finite Element Method),provides theoretical basis to the FEM.Use ANSYS to analyses surface course load stress in different interface.It is found that the interlayer affect load stress of pavement greatly.At the worse-case interface condition,analyses the influence law of different parameters to the load stress of surface load.Based on the result of influence law,obtain the practical formula of surface course load stress of the rigid and semi-rigid base course of cement concrete pavement structure with function layer by regression method.Formula of axle load conversion and fatigue stress coefficients of surface course load stress of the semi-rigid and rigid base course are obtained respectively by fatigue equations and formula of load stress.Analyses the thermal stress of rigid and semi-rigid base course with function layer,obtain the influence law of different parameters to the thermal stress.The thermal stress of base course is very small compara with the thermal stress of surface course.Finally obtain the practical formula of thermal stress of the rigid base and semi-rigid base course of cement concrete pavement by regression method.Based on the analyses of the surface course load stress,get thickness of surface layer thickness and the grassroots coordination between the design,and come to the design method of cement pavement structure.