Research On The Impact Coefficientof The Through Concrete-filled Steel Tube Arch Bridge Based On The Vehicle-bridge Coupled Vibration

Through the interaction between the steel tube and the concrete,The concrete filled steel tubular arch bridge enhances the anti load capacity and reduces the base stress,。It can reduce the weight of the upper structure,save the material and increase the span.At the same time,it has the advantages of good ductility,good seismic performance,better corrosion resistance than steel structure,simple construction and so on.In recent years,it has been widely used in engineering.The vehicle bridge coupling vibration is essentially a random phenomenon of forced vibration.In this paper,the influence factors of dynamic magnification factor are analyzed by the vibration equation of arch bridge under moving load.Then set up the vibration equation of three axis vehicle model with nine degrees of freedom,and the vehicle-bridge coupled vibration equations are also built.The Newmark-method is used to solve the equation.Under the action of the three axle vehicle,the vehicle-bridge coupled vibration modle is built.Numerical simulation is carried out to the response of vehicle bridge interaction.Though controling the change of road roughness and velocity parameters in the program,the influence of road roughness and speed on the impact coefficient of the bridge is analyzed.In the background of the former Lake Bridge,the finite element analysis software ANSYS was used to establish the model of CFST Arch Bridge.Analyse self vibration characteristics of the bridge,the span ratio and the effect of transverse brace on the dynamic characteristics of the bridge is studied.At the same time,use the DHDAS dynamic signal acquisition and analysis system to test the bridge on the spot.Analyse the vibration response of the beam in the middle of the bridge at different driving speeds.The measured values of the impact coefficient of the bridge are obtained by deflection and strain of the bridge.At the same time,identify the modal parameters of the bridge.The measured results and numerical results are compared to verify the correctness and accuracy of the numerical analysis program...