Numerical Simulation For Wind Response Of The Bridge

The development of modern materials, constructions methods and designtheories has resulted in a new generation structure. Such structures are more flexible,lighter weight and low damping, they are more susceptible to the action of wind. Inthe past 20 or 30 years, many kinds of new bridges with special style have been builtin our country. There are many new changes in the structure of these bridges exceptfor their span becomes longer. These changes make the wind effect on the bridgemore remarkable. Wind load effects on the bridge have become to our attention. Inpursuit of economical safe designs, wind load cannot be ignored and it is one of mostimportant factors of designs. For the bridges are becoming more vulnerable to thewind, it is essential to develop realistic analysis procedures for predicting theirbehaviorunderaerodynamicexcitation.Firstly, in this paper the author has tried to outline the background of analysis ofwind resistant and the basal research methods about wind response of bridge. Thecharacteristics of wind have been studied in details in this paper. Simulation of windload have been studied too. Based on finite element software, a numerical solution toinvestigate the dynamical response of the bridge under turbulent wind excitation isdeveloped.Secondly, this paper presents a general discussion of the basic windcharacteristics,includingthecompositionofwind,thecharacteristicsofwindvelocityprofile and the characteristics of turbulent wind velocity. Then, based on the spectraldensityfunction,simulatingthebasicwindbythelinearfiltrationmethod(ARmodel)and the harmony superposition method respectively, based on the platform of Matlabthemulti-point windvelocityhistories program aredeveloped. Inordertoconfirm theprogramisright,spectralanalysisisusedforthesimulatedresult.Thirdly,basedonnumericalsimulationandbridgebeltsuppose,theplanermodelof bridge section is established by computational fluid dynamic method, getting thelaw about coefficient of tri-component force along with the change of angle of attackunder the wind action. Based on the modified Davenport's buffering force equation,turning the wind load on the bridge into the load on each point in the time-domain.Simulating the wind response of DanLa HaiHe Bridge under the design wind speed, in order to confirm the results are available, the comparison between the numericalresultsandtheexperimentresultsisdeveloped.Finally, the wind response of an engineering bridge based on the method isdeveloped,whichliesin TianJinCity.Givingthe evaluationabout thewind-resistancecapability of the bridge after the numerical results is analyzed. Then, somesuggestions arepresented,whichcanimprovethewind-resistancecapabilityofpartialstructure.