Abstract
Time-domain modeling of bridge deck flutter is examined. The frequency dependent aerodynamic self-excited forces acting on a bridge deck are approximated in the Laplace domain by rational functions. Two matrix formulations of the rational function approximation, namely least-squares and minimum-state, are applied to aerodynamic data experimentally or theoretically obtained for various bridge decks. The precision of the approximations and the comparison of the critical wind speed computation by the conventional method and the proposed method are presented.