摘要
丹江口水库特大桥为主跨760 m双塔部分地锚式混合梁斜拉桥,主跨跨中设“无轴力连接装置+大位移伸缩缝”构造。针对主跨跨中处伸缩缝阻尼约束需求,设计一种多级阀并联结构的新型锁定黏滞阻尼装置。建立大桥空间有限元模型进行设计参数优化,开展锁定性能及减振耗能测试,并进行地震作用下伸缩缝运动控制效果仿真分析。结果表明:锁定刚度为150 kN/mm时对伸缩缝有较优的减振效果,且具备较好的可实现性,是理想的设计锁定刚度;锁定性能测试中加载速度大于等于0.5 mm/s时,实现锁定,且锁定位移、锁定刚度均满足设计要求;减振耗能测试中各工况实测阻尼力与理论阻尼力的最大偏差为-6.2%,在规范允许最大偏差±15%以内,表明结构设计与原理的正确性,同时具备较好的速度锁定及黏滞阻尼耗能功能;纵、横向地震作用下,锁定黏滞阻尼器对伸缩缝的运动位移、运动速度均有明显的控制效果。
The Danjiangkou Reservoir Bridge,with a main span of 760 m,is a two-pylon hybrid girder cable-stayed bridge featuring its pairs of end cables anchored to the anchorage-type abutments.The structural details at the midspan of the central span involve an axial-force-free connection device and large-movement expansion joints.To address the damping requirements of the expansion joints at the midspan of central span,a new type viscous damper with lock-up devices is developed,featuring the parallel connection of multi-level valves.Numerical simulation was conducted to optimize the design parameters,tests were carried out to examine the locking as well as vibration mitigation and dissipation performance of the viscous dampers.The control effect of movement of expansion joint under seismic actions was also analyzed.The results demonstrate that with a locking stiffness of 150 kN/mm,the vibration mitigation effect of the viscous dampers at the expansion joints is sound,and vibration mitigation effect is easy to be achieved,indicating 150 kN/mm is an ideal design locking stiffness.In the locking performance test,when the acceleration is equal to or greater than 0.5 mm/s,the locking effect will be achieved,and the movement and stiffness all meet the design requirements.In the vibration mitigation and energy dissipation test,the maximum difference between the measured and theoretical damping forces in different load cases is-6.2%,within the allowable range of±15%,indicating the effectiveness of the structural design and the rationality of the concept,and the viscous dampers have sound velocity locking and energy dissipation capacity.The simulation of the longitudinal and transverse seismic actions indicates that the viscous dampers with lock-up devices can effectively control the movement and moving velocity of the expansion joints.
作者
张汉卫
李东超
刘鹏飞
马长飞
王俊
ZHANG Hanwei;LI Dongchao;LIU Pengfei;MA Changfei;WANG Jun(State Key Laboratory of Bridge Intelligent and Green Construction,Wuhan 430034,China;China Railway Britech Co.,Ltd.,Wuhan 430034,China;China Railway Bridge Science Research Institute,Ltd.,Wuhan 430034,China;Sichuan Tibet Railway Co.,Ltd.,Chengdu 610045,China)
出处
《世界桥梁》
北大核心
2023年第6期98-104,共7页
World Bridges
基金
国家自然科学基金项目(52378147)。
关键词
斜拉桥
锁定黏滞阻尼器
多级阀
参数优化
锁定性能
减振耗能
有限元法
性能试验
cable-stayed bridge
viscous damper with lock-up device
multi-level valve
parameter optimization
locking performance
vibration mitigation and dissipation
finite element method
performance test
