Passive Control Of Long-span Cable-stayed Structure Vibration Based On The Tluid Damper

As the online and lifeline engineering in transportation hub, Long-span bridges structure have the characteristics of gently and a bigger dynamic response under earthquake effect. Fluid damper is a important form of energy shock absorber and was used in aerospace, machinery, military fields. Fluid damper is a kind of non-stiffness, speed related type vibration damper and according to the principle of the fluid motions especially when the fluid through orifice to generated viscous resistance.Fluid damper have has been widely use in engineering practiced because of safety, economy and applicable range, maintenance cost advantages.This paper mainly studies the passive control of fluid damper in longitudinal bridge earthquake effect. Based on the introduction of the principle of energy consumption in fluid damper, which is applied to wuhan tianxingzhou bridge,and establishing the three-dimensional finite element model in ansys and read the waves 200gal El centro to the model tianxingzhou to analysis the characteristics of seismic dynamic. According the unit of conbim14 to imitation fluid damper to control dynamic response of tianxingzhou bridge, so it can meet the safety and durability during military service.This paper introduces the classification of fluid damper and various fluid damper are given the working principle and structure in respectively. The nature of fluid damping is connected with the internal structure such as the conditions of sealing, damping hole and the area of piston rod. In addition, some other factors like the excitation frequency, relative speed, the outside temperature and viscous medium aslo can affect the performance of fluid damper. Among them,the viscous medium play a most inportant role. Fluid damper are broad, which have a few kind of major installation forms in engineeringsuch as diagonal support, herringbone support, lasso type support, scissors type support.This paper analysis the type of medium stagnation body of fluid damper sticking such as Newton fluid and non-newtonian fluid and theirs classification. Introduce several normal restoring force model of fluid damper:linear model, Kelvin model, Maxwell model and Wiechert model.In this paper, ANSYS finite element software is built by 3d model of tianxingzhou bridge, the first to its conduct modal analysis and extract ten modes of tianxingzhou bridge that the basic mode for first order modes. Secondly, the result of structural transient analysis refer the bridge's longitudinal displacement is bigger and far away from the design requirements, so it need to undertake structural vibration control. Use of ANSYS software to simulate the fluid damper on tianxingzhou bridge and read read the waves again to the model on instantaneous analysis, the results showed that longitudinal displacement is greatly reduced by the use of fluid damper on tianxingzhou bridge.