【摘要】 基于预应力索结构的静动力和瞬态分析,对东海某大跨径悬索桥施工期暂态主缆的辅助索制振参数进行了研究,同时研究了用辅助索控制暂态主缆驰振失稳的具体方案,采用了考虑几何非线性影响的有限元数值分析研究方法,总结了驰振及辅助索制振的研究现状,建立了该悬索桥施工期暂态主缆-猫道系统的有限元模型,研究了辅助索位置、布置方式和刚度大小对暂态主缆1阶竖向振动频率的影响;研究了辅助索阻尼、刚度和个数对暂态主缆面内等效阻尼比的影响;最后研究了辅助索控制暂态主缆驰振的具体方案。结果表明:为了提高暂态主缆1阶竖向振动频率,辅助索应该对称竖向布置,且增大辅助索的数目特别是跨中设置辅助索可以较大幅度地提高该频率值;增加辅助索的直径和个数可以较大地增加对暂态主缆的面内制振效果;在该悬索桥中跨12分点处对称竖向布置每组由1根直径为10mm的钢筋组成的11组辅助索时即可控制暂态主缆的驰振失稳。更多还原

【Abstract】 <Title>Galloping vibration control for transient main cables of a long-span suspension bridge at construction stage<Author>LI Sheng-li1,2,OU Jin-ping2,3(1.School of Civil Engineering,Zhengzhou University,Zhengzhou 450001,China;2.School of Civil Engineering,Harbin Institute of Technology,Harbin 150090,China;3.School of Civil and Hydraulic Engineering,Dalian University of Technology,Dalian 116024,China)On the basis of static,dynamic and transient analysis for prestressed cable structures,parametres of controlling for galloping vibration of transient main cables of a long-span suspension bridge at construction stage and a detailed scheme for controlling the galloping vibration with assistant cables were investigated adopting the finite element method considering geometry nonlinearity.The review and prospect for the galloping vibration and controling vibration with assistant cables were summarized,the finite element modeling for the system of transient main cables and catwalk was established,and the influence of the position of assistant cables,their diposed fashion and rigidities upon the first vertical bend vibration frequency of the transient main cables was studied.At the same time,the effect of damping and rigidities of the assistant cables on the equivalent damping ratio of the transient main cables inside plane was studied.In the end,the detailed scheme for controlling the galloping vibration of the transient main cables was studied.Results showed that to increase the 1st vertical vibration frequency of the transient main cables,the assistant cables should be placed symmetrically in the vertical direction and the frequency can be raised through increasing the amount of the assistant cables and setting assistant cables in the middle of the bridge;increasing diameter and amount of assistant cables can improve the vibration of the transient main cables inside plane;the galloping instability at the long-span suspension bridge at construction stage can be controlled when the 11 assistant cables groups are placed symmetrically and vertically at 12 equal division points of the span of the suspension bridge and the assistant cables are made of a reinforcing steel bar of 10mm diameter.<Keywords>suspension bridge;transient main cables;assistant cables;static;dynamic and transient analysis;finite element method;galloping control更多还原