大跨斜拉桥宽幅PK组合梁节段吊装精确匹配技术  

Precise Matching Technique for Segmental Lifting and Erection of Wide PK Composite Girder of Long-Span Cable-Stayed Bridge

作　　者：曹明明 韩洋洋 魏乐永[3] CAO Ming-ming;HAN Yang-yang;WEI Le-yong(China Railway Bridge Science Research Institute,Ltd.,Wuhan 430034,China;Anhui Transportation Holding Group Co.,Ltd.,Hefei 230003,China;CCCC Highway Consultant Co.,Ltd.,Beijing 100088,China)

机构地区：[1]中铁大桥科学研究院有限公司,湖北武汉430034 [2]安徽省交通控股集团有限公司,安徽合肥230003 [3]中交公路规划设计院有限公司,北京100088

出　　处：《桥梁建设》2019年第6期54-59,共6页Bridge Construction

摘　　要：望东长江公路大桥主桥为(78+228+638+228+78)m的双塔双索面组合梁斜拉桥。主梁采用分离双箱PK组合梁,采用桥面吊机节段吊装施工。针对主梁吊装过程中已安装梁段横断面竖向变形导致新吊梁段与已安装梁段无法正常匹配连接的问题,采用ANSYS软件分析梁段吊装拼接过程中产生变形差的原因,提出梁重置换法匹配和T形反力架纠偏的精确匹配技术。通过张拉斜拉索使其承受新吊装梁段的自重,卸载桥面吊机吊装新梁段时产生的前支点力,使已安装梁段的横断面竖向变形回弹归零;然后通过T形反力架施加千斤顶力消除桥面吊机自重引起的竖向变形,使已安装梁段与新吊梁段实现精确匹配。采用梁重置换法和T形反力架纠偏后,该桥施工过程中新吊梁段与已安装梁段实现精确匹配连接。The main bridge of Wangdong Changjiang River Highway Bridge is a two-pylon composite girder cable-stayed bridge with five spans of 78,228,638,228 and 78 m.The stay cables are arranged in double cable planes.The main girder adopts the separated twin-box composite girder with PK section,and the girder segments are lifted and erected by using deck derrick cranes.During the lifting and erection of the main girder,the vertical deformation in the cross section of the already-installed girder segment makes the normal matching connection of the new girder segment and the already-installed girder segment difficult.To address this problem,the software ANSYS is used to analyze the causes of deformation difference during the lifting and connecting process of girder segments,and the precise matching technique of using the girder weight replacement method to match the already-installed segment and new segment and T-shaped reaction frames to rectify offsetting is proposed.The stay cables are tensioned to support the newly-installed segment and to release the front-support force generated during the unloading process of the deck derrick crane and the erection of the new girder segment,with the intention of allowing the vertical deformation in the cross section of the newly-installed girder segment to return to zero.Then,jack forces were applied through the T-shaped reaction frames to eliminate the vertical deformation caused by the self-weight of the deck derrick crane,so as to realize the precise matching of the already-installed girder segment and the new one.By using the girder weight replacement method and the T-shaped reaction frames to rectify offsetting,the precise matching connection of the new girder segments and the already-installed girder segments of the main bridge of Wangdong Changjiang River Highway Bridge was realized.

关 键 词：斜拉桥 PK组合梁 节段吊装 精确匹配 梁重置换法 T形反力架 

分 类 号：U448.27[建筑科学—桥梁与隧道工程] U445.466[交通运输工程—道路与铁道工程]