Analysis Of Wind-Induced Flutter And Buffeting Response Control On Long Span Cable-Stayed Bridge

The famous wind-induced flutter damage of Tacoma bridge make people realize the important position of the bridge wind resistance design in bridge design. With the enhancement of the ability in modern bridge design and construction, bridge span increases, the structure become more flexibility and more sensitive to wind load. Wind resistance of bridge becomes more prominent.With the rapid development of structural vibration control, theoretical research about tuned damping technology becomes more mature and applicative. As the primary tunable damping device, tuned mass damper has been widely applied in the structure of disaster prevention and mitigation engineering. As a flexible and effective damping measure, tuned mass damper can design for different needs. Tuned mass damper system can effectively reduce the dynamic response of structures. So it is widely used in the wind resistant design of high-rise building structure, bridge towers.In this paper, we take a large span cable-stayed bridge as the engineering background, and make research on the following aspects:(1) We research the tuned mass damper working principle and the progress in the application of wind resistance on cable-stayed bridge, and discuss the advantages and disadvantages.(2) We describe the influence of natural wind and fluctuating wind on structure, study aerostatics stability of the bridge and the torsional divergence and lateral buckling critical wind speed calculation method. We get the sample of cable-stayed bridge stochastic wind field history through the harmonic synthesis method, the target power spectrum function artificial simulation of fluctuating wind field, level(downwind) to the pulsating wind spectrum by Simiu spectrum model and vertical fluctuating wind spectrum by Lumley-Pnofsky wind spectrum model. The simulated spectrum and the target spectrum are in good agreement, and the simulation of the spectrum is very close to the target.(3) We establish the damper system and three-dimensional model of the bridge with Using the finite element software ANSYS, analyze the dynamic characteristics and research on the influence of the parameters of tuned mass damper. By adjusting the damping ratio and arrangement of controllers, we make comparative analyses of the influence on the wind-induced flutter. To some extent the layout One and large damping ratio can improve the flutter critical wind speed. The more critical velocity damping ratio, the more critical wind speed increases, but the increase is not obvious.(4) By changing the damper arrangement and parameters, we analyze the influence of damper on wind-induced buffeting of bridge in the lateral direction with the comparative analysis of different layout schemes. The ANSYS calculation results show that: in the lateral direction the displacement and acceleration root variance of the wind-induced buffeting on bridge with dampers reduces and the buffeting control effect relates to the layout of controller. The damping effect of the wind-induced lateral buffeting of bridges will be better when we select reasonable parameters of the controller and optimize the layout of controller.