Analysis On The Coupled Vibration Of Vehicle-bridge For Curved Box-girder Bridge

With the rapid development of urbanization, the development of the traffic is promoted, the curve beam bridge has been widely applied in the city. With the increase of vehicle load weight and speed, and the light of the bridge, the universal application of high pier bridges, the dynamic response of bridges has become a research issue can not be avoided. This paper carries out the study on vehicle bridge coupling vibration of city curved bridge, it has certain engineering application value.The dynamic response in the vehicle dynamic loads of the bridges was analysed profoundly, and with a certain city interchange ramp curved girder bridge was studied as the research object by the numerical simulation.Bridge and vehicle are taken as two separate systems in this thesis, which are connect by the conditions of geometric compatibility and force equilibrium, and a quarter vehicle mode with six parameters and two degree of freedom and a 3-D physical finite element mode have been obtained in this thesis. Then, the effect of parameters, such as pre-stress, curvature radius, constraint formalism and vehicle speed etc, on free vibration characteristics and dynamic responses are analyzed.After the numerical simulation analysis of the changes of various parameters were obtained by the dynamic performance of the curved girder bridge effect, the main conclusions are as follows:(1) Pre-stress of curved girder bridge all affect the displacement, velocity and acceleration response, and with the increase of prestress, the influence is more obvious, and the different order modal frequency values are reduced gradually;(2) Dynamic response fluctuate with the increase of the radius of the curved girder bridge, but it began to stabilize after more than 200 m radius;(3) Dynamic response time history curve tends to smooth and stable as the speed increases.