Experimental Study on Vortex-Induced Vibration Performance and Vibration Suppression Measures of Trough-Shaped Steel Box Girders
To enhance the wind resistance of a bridge with a trough-shaped steel box girder,experimental studies were conducted to investigate the vortex-induced vibration(VIV)performance and vibration suppression measures of the girder.The research focused on a pedestrian landscape bridge's trough-shaped steel box girder,examining its VIV performance under uniform and turbulent wind conditions at+3°,0°,and-3° wind attack angles through sectional wind tunnel tests.Additionally,the study analyzed the effects of vibration suppression measures,including alternately closing railings,changing wedge handrails to circular handrails,and increasing the damping ratio.Results revealed that the original trough-shaped steel box girder section did not meet design code requirements.Under uniform wind flow,vertical bending VIV exceeding limits occurred at all three wind attack angles,with torsional vortex vibration observed at+3° and-3° wind attack angles,with the most unfavorable angle being-3°.In turbulent wind fields,the vertical bending VIV amplitude of the original section decreased by 23％at the most unfavorable wind attack angles,and no significant torsional VIV was observed.The alternately closed railings with wedge-shaped handrails resulted in an increase in the vertical bending VIV amplitude of the girder and degraded the overall VIV performance of the girder.Changing the handrail shape to circular had minimal impact on the VIV performance,but when combined with alternately closed railings,it effectively suppressed VIV.Furthermore,increasing the structural damping ratio significantly suppressed VIV.At a damping ratio of 7‰,the maximum vertical bending VIV amplitude of the girder was reduced to about half the limit value.
NETL
NSTL
万方数据
