| With the rapid development of national economy and road transportation, road traffic volume has been continuously increasing and the loads of bridges bearing are more and more aggravating, in addition, bridges have a trend of long-span and flexibility. Consequently, the safety and usage of bridges are restricted more and more by the dynamic response of bridge, which is the reason why so much attention has been paid to the dynamic research of highway bridges under moving vehicle load.On the base of referring to broad data of domestic and overseas, main research methods and findings of coupling vibration of vehicle-bridge are summarized. Meanwhile, structural dynamics concerned in this thesis is briefly introduced.Based on the assumption of rigid-body dynamics and dynamics of vehicle, the motion equation of seven degree of freedom vehicle model, four degree of freedom vehicle model and two degree of freedom vehicle model are derived. Road roughness, as a main motivation to vehicle, is an important content of the research of coupling vibration of vehicle-bridge. In this thesis, road roughness of grade A,B and C divided by national standard are simulated by the use of Harmonic Addition Method.In this thesis, bridge and vehicle are taken as two separate systems, which are connected by the condition of geometric compatibility condition and force equilibrium. Separation iteration method is used in solving the equation, and solving program is made in Fortran.On the project background of Bo Xi Jin Sha Jiang Bridge, analysis and calculation are done using program made by myself, which is proved to be reliable after comparing the results with experimental data. The influence of different factors to the dynamic response of bridges is analyzed, such as vehicle speed, axle load, car spacings, roadway and road roughness. In the end, some conclusions are obtained which can provide data and theoretical references for the farther research in coupling vibration of vehicle-bridge.
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