Determination of Aerodynamic Admittance Functions of Bridge Decks by Covariance-driven Stochastic SubspaceIdentification Technique

Aerodynamic admittance functions describe the transfer behavior between wind spectra and the spectra of the buffeting forces,which directly determine the precision of the predicted buffeting responses for bridge designs.The covariance-driven stochastic subspace identification is proposed in this paper to determine the aerodynamic admittance functions,which can reduce the corresponding wind tunnel test to one step,and release the restraint of the damping to the precision of identified aerodynamic admittance functions.The determination of aerodynamic admittance functions of the Jiangyin bridge reveals that the proposed technique can conveniently determine the aerodynamic admittance with the demanded precision.