The Stress Analysis And Structure Design Index Research Of The Functional Layer Of Asphalt Under The Concrete Pavement

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.For the property of asphalt mixture,this paper profound analysis the functional layer of asphalt stress status and destruction form,then presents the design method and index of the functional layer of asphalt.The paper analysis the contact status between the cement concrete pavement and the base layer,presents the significant difference between the actual model and the ideal model of the road,and points out the transition layer destruction is an important factor of surface structure destruction,so it is necessary to set up the functional layer of asphalt.Base on the actual use of the function layer of asphalt and the research findings both at home and abroad, builds a suitable finite element analysis model,using three-dimensional eight-node element to calculates the stress status of the functional layer of asphalt for concrete pavement with rigid base layer and semi-rigid base layer,and point out the more reasonable scope of functional layer's thickness and modulus.This paper fits the formula including the maximum shear stress and other parameters.Consider the nature of asphalt mixture has a strong dependence on the time and temperature,this paper using viscoelastic theoretical to analysis functional layer of asphalt's situation of permanent deformation with the changing of the time and temperature,to determine the functional layer of asphalt will not lead to permanent deformation resulting from the end plate empty phenomenon.In the joint of cement concrete pavement,due to the role of partial set,the functional layer of asphalt has the larger shear stress,and the permanent deformation of asphalt mixture is the result of the compression and shear deformation,so in the asphalt design features introduces the shear strength index,and present the structure design method of functional layer of asphalt.