Analytical and experimental study on passive aerodynamic control of flutter of a bridge deck

Considerable attention has been paid to the research of passive and active structural control for wind-induced self-excited vibration of long-span bri dges in recent years. In this paper a passive aerodynamic control of bridge flutter is proposed. The system consists of two additional surfaces to gen erate stabilizing forces. The torsional motion of the surfaces is governed by the additional pendulum attached to the bridge deck. The state-space equ ation of the flutter control system is derived through the rational functio n approximation of the unsteady aerodynamics of the bridge section. The per formance of the control system is evaluated for various parameters of the p endulum and the potential improvement of flutter wind speed is demonstrated through numerical examples. The experimental study showed very good agreem ent with the theoretical prediction for small amplitude motion of the contr ol surfaces. (C) 1999 Elsevier Science Ltd. All rights reserved.