九江长江大桥应用新型TMD抑制吊杆涡振

APPLICATION OF NEW TMD TO SUPPRESSING VORTEX-SHEDDING VIBRATION OF HANGERS OF JIUJIANG BRIDGE OVER VANGTZE RIVER

大跨度刚性梁柔性拱桥的H形吊杆,由于长细比较大,轴力却不甚大,容易发生低风速下的涡激振动,从而导致杆件连接部位的疲劳.应用国外近代开发的阻尼动力吸振器,与其它抑振措施相比,就其工作量、经济性、保持结构外形而言,都要优越得多.本文结合实桥吊杆的涡振问题,采取多个小型的参数分离的阻尼动力吸振器,成功地抑制了吊杆的涡激振动.它的附加质量,调谐比,有效阻尼及抑振倍率均达到振动控制的目标值.

It is well known that H-hanger in large-span bridge of Langer Girder due to its high slenderness-ratio and moderate axial tension is apt to subject to the action of vortex-shedding under low wind speed, thus leading to the fatigue problem at connecting joints of members.The newly developed Tuned Mass Damper ( TMD ) in foreign countries has many advantageous features with regard to economy and aesthetics as compared with other measures of vibration-suppression.This paper describes the successful application of multimicro parameter-separating TMD in suppressing vortex-shedding vibration of hangers in an actual bridge, whose construction has just completed in last year.The added mass, the tuning ratio, the effective damping as well as the vibration-suppresion I multiple have all reached the target values of vibration-control.