Research On Seismic Response Control Of Long Span Suspension

With the development of long-span suspension bridge and vibration control technology, the vibration control of long-span suspension bridge has become a new topic in the engineering field. In the past, many scholars'research mainly focused on how to control the response in the wind. With the shocks of earthquake on the safety of long-span suspension bridge, the seismic response control issues of long-span suspension bridge are also increasingly prominent. The displacement-control issues of the central span of girder of the long-span suspension bridge including horizontal, vertical and torsional vibration are mainly researched.Although the applications of Tuned mass damper(TMD)on bridge have many successful cases, designing a reasonable TMD for long-span suspension bridge has many problems. A research-model is established according to the data of Jiangyin bridge and a TMD for long-span suspension bridge borrowing the ideas of lever-type TMD based on the dynamic characteristics analysis is designed. TMD control analysis is made under the actual situation of the research-model. The result of TMD control analysis shows that TMD has some effect on the displacement of central span of girder in three directions, but its control effect is limited and sensitive to the seismic records.Active control of seismic response control applied on bridges has been researched by many scholars, but the control algorithms'computing efficiency and the time-delay problems affect its far-reaching adoption, especially for such a long-span suspension bridge with a large degree of freedom system. Instantaneous optimal control algorithm based on Wilson-θmethod is proposed. This algorithm eliminates the time-delay computing the optimal control and it has higher efficiency. Active control program is compiled and anther research-model is established by self program MockCool according to the data of Kwang-An Grand Bridge and active control analysis of this bridge is made. The result of active control analysis shows that instantaneous optimal control algorithm based on Wilson-θmethod has good control performance on the displacement of central span of girder in three directions. The effect both the horizontal and the vertical can reach more than 90%. Besides, the sensitivity of seismic records is not strong to the weight coefficient.TMD passive control and AMD Active control of the long-span suspension bridge under earthquake has been researched, hoping to provide reference for the research on vibration control of same kind of bridge.