摘要
为选取风荷载及随机车流联合作用下合适的粘滞阻尼器参数,以温州市七都大桥为背景,基于变参数阻尼器的风-车-桥耦合振动分析系统,建立大桥有限元模型,研究风荷载、特定车载、风荷载及随机车流联合作用下不同参数粘滞阻尼器的减振效果。结果表明:风荷载下粘滞阻尼器对梁端、塔顶等部位纵向位移减振效率随速度指数α增大而减小,随阻尼系数C增大而增大,对塔梁间纵向相对位移减振效果最显著;特定车载下梁端纵向位移减振效率随速度指数α增大而增大,随阻尼系数C增大而减小,而塔顶纵向位移、塔梁间纵向相对位移随速度指数α增大而减小、随阻尼系数C增大而增大;风荷载及随机车流联合作用下粘滞阻尼器对梁端纵向位移的减振效率随速度指数α减小而增大,随阻尼系数C增大而增大;综合考虑减振效果及经济性,确定温州市七都大桥粘滞阻尼器优化阻尼系数C为1500 kN·(m/s)-α、速度指数α为0.1。
To determine the proper parameters for viscous dampers under combined wind loads and random traffic flow,a finite element model based on Qidu Bridge in Wezhou City was built,with a wind-vehicle-bridge coupling analysis system involving dampers of variable parameters.The vibration effects of viscous dampers set with different parameters were studied in the contexts of pure wind loads,pure specific vehicle loads as well as the combined wind loads and random traffic flow.The results show that under wind loads,vibration mitigation efficiency of viscous dampers for the girder-end and pylon-top longitudinal movement decreases as the increase of speed index α,but increases as the increase of damping coefficient C,and the damping effect is most significant on the longitudinal relative movement between pylon and girder.Under specific vehicle loads,the vibration mitigation efficiency of girder-end longitudinal movement increases along with the increase of speed index α,but decreases as the increase of damping coefficient C;the pylon-top longitudinal displacement and longitudinal relative movement between pylon and girder decreases as the increase of speed index α,but increases along with the increase of damping coefficient C.Under the combined wind loads and random traffic flow,the vibration mitigation efficiency of viscous dampers on girder-end longitudinal movement increases as the decrease of speed index α,but increases along with the increase of damping coefficient C.To realize the balance of vibration mitigation effect and economy,the optimized damping coefficient Cof viscous dampers on the Qidu Bridge in Wenzhou City is set at 1 500 kN·(m/s)-α,when the speed index α is 0.1.
作者
朱勇
荆国强
吴肖波
张路
宋腾腾
ZHU Yong;JING Guo-qiang;WU Xiao-bo;ZHANG Lu;SONG Teng-teng(Wenzhou City Construction Development Group Co.,Ltd.,Wenzhou 325000,China;State Key Laboratory for Health and Safety of Bridge Structures,Wuhan 430034,China;School of Highway,Chang′an University,Xi′an 710064,China)
出处
《桥梁建设》
EI
CSCD
北大核心
2020年第6期59-65,共7页
Bridge Construction
基金
湖北省技术创新专项项目(2018AAA029)。
关键词
桥梁工程
风-车-桥耦合系统
粘滞阻尼器
减振效果
优化设计
有限元法
bridge engineering
wind-vehicle-bridge coupling system
viscous damper
vibration mitigation effect
optimization design
finite element method
