ABSTRACT
Flutter is one of the significant wind-induced vibrations of modern long-span bridges, and the aerodynamic derivatives (ADs) describe the aerodynamic performance of bridge structures. The ADs of the bridge deck can be determined uniquely on condition that the complex modal parameter so the system at one reduced frequency is obtained. Also, the stochastic subspace identification (SSI) has better anti-noise ability and higher accuracy of modal parameter identification. The modal parameters under the same reduced wind speed were obtained from the linear interpolation through the identified modal parameter database, and the ADs were then determined based on the unique idea. The feasibility and applicability of this newly proposed method are verified by a wind tunnel test of the two-degree-of-freedom (2DoF) spring suspension section model. Finally, the effects of turbulence intensity and integral scale of turbulence on ADs of closed-box decks were investigated in the three grid-generated turbulent wind fields.
