Study On Seismic Response And Passive Vibration Control Of Large-span Arch Bridge

Arch bridge is a common structure that has been widely built in our nation (especially in the southeast region). In recent years, the location in areas of frequent eruption of earthquake and the poor seismic performance of arch bridge itself make the issue of how to reduce the seismic response of arch bridge more significant. In respect to seismic perfomance of long-span reinforced concrete box-typed arch bridge and the passive vibration control, the main studies are as follows: 1.The seismic response study of long-span reinforced concrete box-typed arch bridges. The dynamic behaviour of the structure itself has been researched in this paper by establishing the dynamic finite element modal of Nimu bridge; Through spectrum analysis, time-marching analysis and radom vibration analysis,the seismic performance of arch bridge under one-dimension and multi-dimension excitation has been analyzed. 2.The study of vibration control of long-span arch bridges by TMD. First, the main vibration mode is confirmed by the method of modal mass ratio and response power spectrum, and then the optimal parameters of TMD is attained by the optimal theory based on radom vibration which includes optimal frequency ratio, optimal damper ratio, optimal location of TMD and the effective weight of the TMD mass. Finally, the fact that fixing TMD in arch bridge is a effective method to reduce the seismic response of the structure is verified by the time-marching analysis result. 3.The scheme study of structure vibration control by TMD. Two TMD-fixed schemes adapting to different situations have been proposed in this paper, and the influence of the structure mechanical behavior has been studied when TMD is fixed in arch bridge.