Flutter Analysis Using Quasi-Steady Time-Domain Flutter Derivatives

To be able to perform nonlinear flutter analyses for bridges, time‐domain approaches should be used instead of Scanlan’s formulation of self‐excited forces. Thus, this paper addresses the development and validation of a modified quasi‐steady time‐domain model similar to Scanlan’s approach that is based on the velocity and acceleration of the bridge deck. In this formulation, quasi‐steady time‐domain flutter derivatives measured in the wind tunnel through forced‐vibration tests at absolute constant velocity and acceleration are used. For this, a unique test rig, which can be used either for free‐ or forced‐vibration tests, was utilized. By measuring the time‐domain flutter derivatives of the Great Belt Bridge, their nondimensionalization with respect to the bridge‐deck width, velocity and acceleration of the deck is validated. Then, time‐domain flutter analyses are performed using this new model. They agree with the experimental critical speed and the prediction using Scanlan’s model.