摘要
丹江口水库特大桥为主跨760 m的双塔双索面部分地锚式混合梁斜拉桥,边中跨比为0.2,采用梁塔分离、梁台固结的结构体系。根据主桥结构体系受力需要,主梁在跨中位置断开,设置跨中无轴力连接装置+伸缩装置构造。无轴力连接装置由导梁、外部大箱梁(H梁段和H′梁段)、竖向及横向支座系统组成,导梁长13.68 m。无轴力连接装置现场安装采用导梁跨中分段(2×6.84 m)拼装、外部大箱梁逐缝合龙的施工方法。首先在总拼场地进行无轴力连接装置工厂化预拼装,并安装竖向及横向支座系统,拼装完成后将导梁断开,回位至H梁段和H′梁段进行转运;然后现场吊装匹配连接H梁段,并将H梁段内部导梁向岸侧拖动固定;之后起吊H′梁段并与前置G梁段软连接;再进行H梁段和H′梁段导梁匹配连接;导梁匹配连接完成后进行H′梁段匹配连接;最后进行斜拉索放张、桥面吊机拆除。
The Danjiangkou Reservoir Bridge is a hybrid girder cable-stayed bridge featuring its pairs of earth-anchored stay cables.The bridge has two pylons that create a main span of 760 m and a side span-to-main span ratio of 0.2.The stay cables are arranged in double cable planes.Fixed with the abutments,instead of the pylons,the superstructure is equipped with an axial-force-free connector and expansion devices at midspan to fulfil the load bearing requirements of the structure.The axial-force-free connector consists of a 13.68 m-long guide beam,external large box beam(including H and H′sections),and vertical and transverse bearings.During installation,the two sections(each 6.84 m long)of the guide beam were assembled on site and the external large box beam was stitched joint by joint.Firstly,the axial-force-free connector was assembled to take shape in the yard,the vertical and transverse bearings were installed,afterwards,the guide beam was halved and moved back to large external box sections H and H′for transfer.Then,the H section was hoisted and connected on site,and the guide beam section inside the H section was dragged towards the bank for fixity.Afterwards,the H′section was hoisted to softly connect with the front girder section G.Subsequently,the guide beam sections inside the external large box beam sections H and H′were connected.After the connection of guide beam,the H′section was match-connected.At last,the stay cables were de-tensioned,and the deck cranes were dismantled.
作者
刘朝辉
周范武
于得安
高海涛
LIU Zhaohui;ZHOU Fanwu;YU Dean;GAO Haitao(Hubei Jiaotou Shixi Expressway Co.,Ltd.,Shiyan 442000,China;CCCC Second Harbor Engineering Co.,Ltd.,Wuhan 430040,China)
出处
《世界桥梁》
北大核心
2024年第3期36-41,共6页
World Bridges
关键词
部分地锚式斜拉桥
无轴力连接装置
导梁
外部大箱梁
分段拼装
逐缝合龙
施工技术
partially earth-anchored cable-stayed bridge
axial-force-free connector
guide beam
external large box girder
sectional assembly
joint-by-joint closure
construction technique
