Mechanical Study On AC+CRCP Bridge Deck Pavement Reconstruction On Two-Way Curved Arch Bridge

Two-way curved arch bridge is widely used in the south of the Yangtze River in China.From longitudinal section,the bridge superstructure is mainly composed of main arch ring,abdominal arch ring,standing pillar,side wall and so on.Compared with ordinary bridge deck pavement,two-way curved arch bridge deck pavement not only meets the functional requirements of sliding resistance,smooth,abrasion resistant and waterproof,but also needs enough strength and stiffness to adapt the deformation caused by load stress and temperature stress.Theoretical researches and numerical simulation analysis on the steel bridge and cement concrete bridge deck pavement have been made at home and abroad.However,there are few researches on two-way curved arch bridge deck pavement.Researches on composite pavement structure on two-way curved arch bridge are even fewer.Thus,it is necessary to analyze the mechanical behavior of composite pavement structure on two-way curved arch bridge and determine the calculation method of structural stress,to provide theoretical basis and reference to the engineering application.Combined with the practical reconstruction project of Nanjing Yangtze River Bridge,the composite deck pavement of dense-graded asphalt concrete(AC)surface layer and continuously reinforced concrete pavement(CRCP)layer is analyzed in this paper.Based on the finite element method,a three-dimensional finite element model of the whole two-way curved arch bridge with composite pavement structure is built.The reliability of model is verified.The mechanical behavior of composite pavement structure on two-way curved arch bridge under vehicle loading is analyzed.The stress,strain and displacement of composite pavement structure with different loading positions are analyzed.The critical load position and the reasonable longitudinal continuous mode are determined.The influence of temperature gradient and pavement structure parameters on mechanical response of composite pavement structure is analyzed.On this basis,combined with the results of sensitivity analysis,formulas of the maximum load stress and temperature stress of CRCP of composite pavement structure on two-way curved arch bridge are returned based on regression analysis.Formulas of fatigue stress of CRCP are derived.Finally,considering the coupling effect of load and temperature,the formula of maximum interlayer shear stress of composite pavement structure on two-way curved arch bridge is returned.Firstly,the mechanical response of composite pavement structure on two-way curved arch bridge under vehicle loading is analyzed.Based on the finite element method,the ABAQUS finite element software is used to build a three-dimensional finite element model of composite pavement structure on two-way curved arch bridge under vehicle loading.The reliability of model is verified.The mechanical responses of composite pavement structure with different loading positions are compared.The critical load position is determined.Then,the impact of longitudinal continuous mode on mechanical response of composite pavement structure is analyzed.The reasonable longitudinal continuous mode is determined.On this basis,the influence of pavement structure parameters on the mechanical response of composite pavement structure is analyzed.Secondly,mechanical response of composite pavement structure on two-way curved arch bridge under linear temperature gradient is analyzed.Based on the finite element method and the thermodynamics theory,a three-dimensional finite element model of composite pavement structure on two-way curved arch bridge under temperature gradient is built.The reliability of model is verified.On this basis,the influence of temperature gradient and pavement structure parameters on mechanical response of composite pavement structure is analyzed.Thirdly,the fatigue stress of CRCP of composite pavement structure on two-way curved arch bridge is researched.Based on the orthogonal design method and the multivariate statistical regression method,formulas of the maximum load stress and temperature stress of CRCP of composite pavement structure are returned.On this basis,combined with the current national standard of China,formulas of the load fatigue stress and temperature fatigue stress of CRCP are returned considering the fatigue properties of cement concrete materials.Finally,the maximum interlayer shear stress of composite pavement structure on two-way curved arch bridge is researched.Considering the interlayer shear failure of composite pavement structure,based on the finite element method and the regression analysis,the formula of the maximum interlayer shear stress of composite pavement structure under the coupling effect of load and temperature is returned.