2016年11月下第45卷第22期
DOI:10.7672/sgjs2016220099
施工技术
CONSTRUCTION TECHNOLOGY
纵向双吊杆自锚式悬索桥吊杆张力控制方法
戴小松，秦建刚，周强新
（中建三局投资发展公司，湖北武汉430071）
[摘要】武汉江汉六桥主桥为（48+57+110+252+110+57+48)m自铺式叠合梁悬索桥，全桥共设61对吊杆，同一吊点设置纵向双吊杆。为了解决体系转换过程中最不利工况同一吊点的双吊杆受力不均造成接长杆索力可能超限而滑脱现象，提出利用有限元软件MIDAS建立单吊杆及双吊杆正装模型，从单吊杆模型计算得到各阶段各吊杆的吊杆力；在双吊杆模型中，以单吊杆模型中吊杆力的均分力建立某根吊杆最大吊杆力阶段的一次成型的施工阶段，得到各吊杆的无应力长度，以无应力状态法控制，得到各施工阶段双吊杆各自的张拉力。此控制方法实桥应
用后双吊杆的索力较均匀，可以省去成桥后由于索力不均带来的大量而繁项的调索工作。【关键词】桥梁工程；悬索桥；自锚式悬索桥；双吊杆；有限元分析
［中图分类号］U448.25
【文献标识码］A
［文章编号］1002-8498(2016)22-0099-04
SuspenderTensionControlMethodofSelf-anchoredSuspension
BridgewithVerticalDoubleSuspender
Dai Xiaosong,Qin Jiangang,Zhou Qiangxin
(Inpestment and Derelopment Company of China Construction Third Engineering Bureau
Wuhan,Hubei430071,China）
Abstract : Wuhan Jianghan Sixth Bridge is a self-anchored compositing girder suspension bridge, its span is (48 +57 +110 +252 + 110 +57 +48)m. It sets 61 suspenders with vertical double suspender in the same hanging point. In order to solve the problem that in the most unfavorable condition of system transformation process the force of double suspender is not evenly which can cause that the force of extension bar exceeds the limit and then slide, establishment of single suspender and double suspender bridge model using the finite element software MIDAS is put forward. Calculating the suspender force at some stage through a single suspender model, using the average value of the suspender force in the previous step establishes a single stage deforming of the same stage in the double suspender model, and gets the unstressed length of each suspender. Then using the unstressed state control method can get each eonrooroasosresoooeraoaa application of the method, which can save large and complicated cable adjustment work due to uneven stress in completed bridge stage.
Key words : bridges ; suspension bridges ; self-anchored bridges ; double suspenders ; finite element analysis
0
引言
武汉江汉六桥由于航道管理部门要求必须保
证90m通航孔，故江中只能设置4个临时墩，桥面板只能分阶段叠合，吊杆不得不分级张拉，体系转换过程中主缆大变形效应更明显，由于吊杆的临时锚固接长杆受力有限制，一且双吊杆的合力接近限值，如果双吊杆的受力不均，就会造成其中1根吊杆
【作者简介］戴小松，高级工程师，E-mail：daixs@163.com【收稿日期]月方数据
99
力超限，进而造成接长杆滑脱危险，甚至引起连锁反应，因此有必要对最不利工况下双吊杆的吊杆力
均匀性进行控制。工程概况
江汉六桥主桥为（48+57+110+252+110+ 57+48）m自锚式叠合梁悬索桥，主跨失跨比为1/ 6，矢高42m，其立面布置如图1所示。桥塔为框架型结构，由下塔柱、中塔柱、上塔柱及塔顶横梁4部分组成,其中中塔柱及塔顶横梁为钢结构，其余为