PROBLEMATICS IN FORMULATION OF WIND-FORCE MODELS FOR BRIDGE DECKS

The present paper concentrates on two dimensional static and dynamic fluid-structure force effects. Forces acting on elongated bluff bodies like long-span bridge decks have been described by theories and analytical formats strongly influenced by analogous expressions found in two-dimensional airfoil theory. These theories are first reviewed. The resulting formats are seen to contain some formalisms that may overly constrain the force descriptions when applied to bluff bodies. The particular circumstances where this is evident are pointed out. An important point of the present paper is to emphasize the need to employ a format that can be applied directly to design studies of real bridges and that can be reinforced by experiment. The nature of experiments needed to support design calculations for bridge decks is briefly discussed. In sum, the paper offers an integrated version of aeroelastic theory applicable to long, flexible, bluff bodies such as suspended-span bridges. Emphasis is placed upon origins and legacies of aeronautical theory and upon identification of the key parameters that must be measured experimentally in the present context.