Suspension Bridge Flutter for Girders with Separate Control Flaps

Abstract

Active vibration control of long span suspension bridge flutter using separate control flaps (SFSC) has shown to increase effectively the critical wind speed of the bridges. In this paper, an SFSC calculation based on modal equations of the vertical and torsional motions of the bridge girder including the flaps is presented. The length of the flaps attached to the girder, the flap configuration, and the flap rotational angles are parameters used to increase the critical wind speed of the bridge. To illustrate the theory a numerical example is shown for a suspension bridge of 1,000 + 2,500 + 1,000 m span based on the Great Belt Bridge streamlined girder.