Analysis of damper effect on cable-stayed bridge using finite element simulation

摘要

Cable-stayed bridges generally having common defects such as excessive vibration due to wind action, corrosion andudfatigue occurred at the cables supporting member. This study presents two different approaches for the demonstrationudof the damping effect due to wind action on cable-stayed bridge. The fi rst approach uses a simplifi ed analysis method toudstudy the reaction force at the cable end. A beam element was adopted for modelling the cables and a plate element forudmodelling the bridge’s deck. The second approach is based on the selected damper system applied at the cable end touddetermine the reaction response at the bridge models. Two methods are presented in this report with the consideration ofudbridge geometric effect. The effect of pretension of the cable and the exact treatment of cable sag with the cable weightudis ignored. A numerical calculation has been carried out in determining the nominal transverse wind load, the nominaludlongitudinal wind load on deck and the nominal longitudinal wind load on cables in accordance to the current code ofudpractice. The results generated from MIDAS Civil software have been used for comparing the analysis results. The stiffnessudcoeffi cient for the selected rubber damper type was being modelled at the cable end to examine the effect of nominal andudcombined wind action at critical locations. The effectiveness of using the rubber damper to suppress the effects of windudwas investigated through superposition of these rubber dampers at the maximum reactions at the cable end. It was foundudthat the damper system adapted on the cable-stays has signifi cant infl uence on suppressing the action due to wind.