摘要
针对大跨度斜拉桥施工期间斜拉索减振的特定要求,研发一种由钢丝绳与剪切型高阻尼橡胶阻尼装置串联组成的斜拉索临时阻尼器。首先基于Kelvin模型理论推导了斜拉索-临时阻尼器的振动方程,利用复模态分解得到斜拉索的对数衰减率;然后通过高阻尼橡胶阻尼装置的性能试验、斜拉索-临时阻尼器振动系统的数值模拟以及实桥测试,开展临时阻尼器减振性能研究。结果表明:橡胶阻尼装置的储能刚度和附加阻尼系数随减振橡胶剪切面积的增加而增大;实桥试验索减振效果较好,设计的临时阻尼器可以有效抑制施工期间斜拉索的振动,且安装拆卸方便;在平潭海峡公铁大桥的应用过程中,斜拉索-临时阻尼器系统的对数衰减率达到3%以上,减振效果良好;该阻尼器作为大跨度斜拉桥施工期斜拉索临时减振装置,具有良好的推广和使用价值。
Specific vibration mitigation requirements are also necessary for the long-span cable-stayed bridge in the construction stage.In this paper,a kind of temporary stay cable dampers is introduced.An individual damper consists of a steel wire rope and shear-type high-damping rubber,and the two are in series connection.The stay cable-temporary damper vibration equation is first derived based on the Kelvin model theory,using complex modal decomposition to obtain the logarithmic decrements of stay cables.Then,the vibration suppression performance of the temporary dampers are studied via tests and numerical simulation,including the tests to examine the property of the high-damping rubber device,numerical simulation of the stay cable-temporary damping system and testing on real bridges.It is shown that the energy storage stiffness and additional damping coefficient of the damping device are positively correlated with the shearing area of the vibration suppression rubber,namely larger shearing area will lead to greater energy storage stiffness and damping coefficient.In the case of Pingtan Straits Rail-cum-Road Bridge,the logarithmic decrement of the stay cable-temporary damping system reached above 3%,exhibiting sound vibration damping effect.With composition for easy installation and demolition,the proposed damper can be used as a temporary vibration suppression device for stay cables of long-span cable-stayed bridge in construction stage and will have great potential for wide application.
作者
李东超
赵海威
杨林
LI Dong-chao;ZHAO Hai-wei;YANG Lin(State Key Laboratory for Health and Safety of Bridge Structures,Wuhan 430034,China;China Railway Britech Co.,Ltd.,Wuhan 430034,China)
出处
《世界桥梁》
北大核心
2021年第3期91-96,共6页
World Bridges
基金
湖北省技术创新专项项目(2018AAA029)。
关键词
斜拉桥
斜拉索
施工期
临时阻尼器
高阻尼橡胶
对数衰减率
性能试验
实桥测试
cable-stayed bridge
stay cable
construction stage
temporary damper
high-damping rubber
logarithmic decrement
performance test
testing on real bridge
