Three-Dimensional Effect of Feedback Controlled Winglets in Flutter Suppression of Suspension Bridge.

To account for the influence of winglet's arrangement length and installing position along the longitudinal direction of bridge deck, as well as actuators quantities on flutter control effect, a three-dimensional model of deck-winglet system was been derived in state space domain, and a model reduction method was also discussed to enhance control efficiency. Then, a suspension bridge with a main span of 3 000 m was used to investigate the control effect of active winglets, and to explore the influence of winglet length and actuator quantity on flutter control effect. Finally, the flutter and buffeting performance of winglet itself was investigated. The simulation results shows that the modes involved in flutter analysis should be determined according to mode-energy participation ratio. When installing a pair of winglets whose width is 10% of bridge deck, the critical wind speed of bridge deck may be twice of a non-controlled condition. In addition, the critical wind speed increases by increasing the length of winglets and actuator quantity. However, the critical wind speed may remain constant once the winglet length and actuator quantity exceed a critical value. By ensuring the critical wind speed of winglet itself is higher than bridge deck, winglet's width should be less than 10% of bridge deck's width, and the independent length winglet is proposed to be shorter than 15% of the length of center span of bridge deck. [ABSTRACT FROM AUTHOR]