海上大跨度斜拉桥渡台风致振动控制研究  

Research on Typhoon-Induced Vibration Control of Long-Span Sea-Crossing Cable-Stayed Bridge

作　　者：曹海清 谢朋林 曾银勇 李林挺 周俊龙 CAO Hai-qing;XIE Peng-lin;ZENG Yin-yong;LI Lin-ting;ZHOU Jun-long(China State Construction Bridge Co. ,Ltd. ,Chongqing 402260,China;China Construction Sixth Engineering Bureau Co. ,Ltd. ,Tianjin 300171,China)

机构地区：[1]中建桥梁有限公司,重庆402260 [2]中国建筑第六工程局有限公司,天津300171

出　　处：《世界桥梁》2022年第2期78-83,共6页World Bridges

摘　　要：为确保在建海上大跨度斜拉桥在台风期施工时安全渡台,以宁波舟山港主通道项目舟岱大桥南通航孔桥为背景,对大跨度斜拉桥钢箱梁悬臂施工状态下的抗风措施及其抗风性能进行研究。对于台风来临前未能合龙斜拉桥钢箱梁,在钢箱梁两悬臂端采用10组由7根Φ15.2 mm钢绞线组成的抗风索相连作为约束,并在桥塔位置加设横向、纵向钢管连接钢箱梁与塔身,在竖向设置预应力钢绞线共同组成钢箱梁临时锚固系统。采用MIDAS Civil软件建立桥梁最大悬臂状态有限元模型,对不设置抗风索和增设抗风索的结构抖振位移和内力进行计算。结果表明:抗风索能够降低斜拉桥钢箱梁在台风作用下的抖振位移及内力,理论上布置抗风索后钢箱梁在51.1 m/s设计风速时的内力值可以降低到35 m/s风速时的水平,结构安全;设计风速下,单束抗风索内力最大值低于其设计强度,满足自身强度要求;在不同风速下,抗风索对钢箱梁临时锚固内力的影响效果不同。How to keep the long-span cable-stayed bridge under construction safe during a typhoon is studied.Based on the engineering practice of the south navigable bridge of Ningbo-Zhoushan Port Main Channel Project,the wind resistant measures and the related wind resistant effect of the long-span cable-stayed bridge during the cantilever construction of steel box girders were examined.For the superstructure of the cable-stayed bridge that could not be closed before the typhoon,it is recommended to connect the two cantilever ends with 10 groups of wind cables,each consisting of 7,15.2 mm-diameter steel strands,add transverse and longitudinal steel pipes to connect the steel box girder and the pylon in the pylon zone,and arrange prestressing tendons in the vertical direction,which all together forms the temporary anchor system of the superstructure.The finite element model of the bridge in the maximum cantilever state was established by MIDAS Civil,to calculate the buffeting-induced displacement and internal force of the structure with and without wind cables.The results show that cables can reduce the buffeting-induced displacement and internal force of the superstructure under the action of typhoon.With wind cables,the internal force of steel box girder at the design wind speed of 51.1 m/s can be theoretically decreased to the level at the wind speed of 35 m/s,indicating that the structure is safe.At the design speed,the maximum internal force of individual stay cable is less than the design value and sufficient to sustain its safety.Under different wind speeds,the wind cables will exert different effect on the internal force of temporary anchoring system of superstructure.

关 键 词：斜拉桥 钢箱梁 抗风索 台风 抗风性能 抖振响应 有限元法 

分 类 号：U448.27[建筑科学—桥梁与隧道工程] U441.3[交通运输工程—道路与铁道工程]