Computational method for the prediction of dynamic response oflong-span bridges due to unsteady wind load

摘要

A two step computational method is proposed to predict the dynamicresponse of the long span bridges by unsteady wind loads due to vortexshedding. Computational fluid dynamics (CFD) analysis using a twodimensional model of the bridge deck section are carried out to evaluatethe unsteady wind loads on the bridge deck. Three dimensional dynamicanalysis of the bridge under unsteady wind loads are followed toinvestigate vortex excited oscillations of the bridge. For an economicalapplication of the computational method proposed, an approximatecalculation method of unsteady wind loads is presented. Reasonableagreements are observed between the predictions by the computationalanalyses and the existing wind tunnel measurements, and between theprediction by unsteady wind loads calculated through CFD and theprediction by approximated unsteady wind loads