Research On Vibration And Control Of Long Span Suspension Bridge

As a purpose of protecting the joints of long span bridge and saving survice cost and promoting the durability of bridges,The 1000-meter main span steel truss suspension bridge is selected. The bridge is called Baiyang Yangtze River Bridge in the highway from Yichang to Zhangjiajie. The moving vehicle loads that impact the joints greatest is the center point.The earthquake action is considerate as a complement of the analysis of steel suspension bridge. In addition,fluid viscous damper is added in this analysis.The longitudinal displacement of main beam under the influence of normal moving vehicle loads is researched.Also,its influences is what is researched.In order to take the most advantage of the fluid viscous damper,a single span suspension bridge is the study object in this paper. Three-dimensional model of strcture is builded based on the method of finite element analysis. The process of vehicles crossing the bridge and the earthquake action is simulated.The mothod of nonlinear time history analysis is used to research the longitudinal displacement of suspension bridge with or without the fluid viscous damper. In addition,the parameter of fluid viscous damper that controls the longitudinal displacement of main beam is researched to distinguish who is the best.On this basis, The design and selective of the fluid viscous damper of long span suspension bridge that can be a reference for bridge engineering design is summarized.In this paper,the research background and the significance of the topic is firstly introduced. Secondly, the development and characteristic of suspension bridge and steel truss suspension bridge is simply discoursed. In addition,the famous example of suspension bridge and research status which is domestic and foreign is included in this paper. Furthermore,the finite element model of 1000-meter main span steel truss suspension bridge is described in this research.Besides,the analysis of static and dynamic force characteristics of the model and the response of this structure at earthquake action which is not included fluid viscous damper is described in this paper. According to the analysis above, the time history analysis of moving vehicle loads of this 1000-meter main span steel truss suspension bridge is discussed in this research.In this chapter,the moduleof the time history analysis of moving vehicle loads of Midas------finite element software is transferd. Finally,the parameter selection and optimization of fluid viscous damper of1000-meter main span steel truss suspension bridge is described.The chapter is the emphasis of this research in this paper. In this chapter,The working principle and parameter sensitivity analysis of fluid viscous damper is described firstly.And then the fluid viscous damper is added to the model. According to the existing literature,a serious of parameter values of fluid viscous damper is selected.Finally,the conclusion is that the best parameter value of fluid viscous damper is known which is under the production permit through selection of parameters.In this condition,the longitudinal displacement of this 1000-meter main span steel truss suspension bridge that is under the moving vehicle loads and earthquake action is the least.So the research on vibaration and control of long span suspension bridge is solved.