Computer simulation of buffeting actions of suspension bridges under turbulent wind

Suspension bridges are long-span flexible structures susceptible to various types of wind induced vibrations such as buffeting actions. In this paper, a three dimensional finite-element model formulated to deal with suspension bridges under turbulent wind is presented. In this model, all sources of geometric nonlinearity such as cable sag, force-bending moment interaction in the bridge deck and towers, and changes of bridge geometry due to large displacements, are fully considered. The wind loads, composed of steady-state wind loads, buffeting loads and self-excited loads, are converted into time domain by using the computer simulation technique. The Newmark-β step by step numerical integration algorithm is used to calculate the buffeting responses of bridges. Compared with the results obtained by classical buffeting theory, the validity of the simulation is proved.