The Research And Program Realization Of Vertical Coupling Vibration Of Vehicle-bridge In The Long-span Bridge

The moving vehicle on a bridge may cause the vibration of the bridge and vibration of the bridge may affect the running of the vehicle at the same time, which will raise the problem of the coupled vibration of vehicle -bridge system. With increasing of speed of trains and lightening and enlarging of bridge structures, the problem of the coupled vibration of the train-bridge system becomes more serious increasingly. Therefore, research on vehicle-bridge dynamic analysis is becoming a focus of increasing interst in the field engineering.To analyze the complex Vertical coupled vibration between bridge and vehicles effectively, the ralationship of track irregularity-vehicle-bridge is coupled to a whole dynamics system, and a full theoretical is established. In this thesis, the main research work is as follows:(1) First of all, the present status on the studies of the coupled vibration of train-bridge system is overviewed from the aspects of analytical models, wheel\rail solving methods, and the perspectives about the research in this field is indicated.(2) A model about the Vertical coupled vibration between the train and the bridge is built, and the equations of dynamic equilibrium of the coupled vibration of the train-bridge system are deduced through the compatibility conditions of displacement. Coupling Vibration relationship is formed, on the basis of that, formed a series of Vehicle—Bridge control equations, and by using numerical method, we get detailed solution procedure.(3) It is very important to get accurate self-vibration frequency when analyzing bridge structure with the finite element method. The self-vibration frequency of bridge is introduced briefly.(4) Running safety and comfort assess index of train moving on large span bridges is introduced, and all kinds of index are discussed and compared with each other in details.(5) A FORTRAN program for analyzing the Vertical coupled vibration of the train-bridge system is generated, and Taking a Cable-stayed bridge in light railway as the example, the dynamic responses of Cable-stayed Bridge are calculated under the track irregularity when the train is passing the bridge.The assessment on the safety of the bridge is carried out, and influence of the velocity of the train on the dynamic responses of the bridge is explored. By using the FORTRAN program, it is able to analyze high-speed Vehicle-Bridge System dynamics characteristics effectively, it also could provide the oretical basis for high-speed engineering disign.