南广铁路西江特大桥钢箱拱肋吊装施工过程仿真分析  

Simulation Analysis of Construction Process of Steel Box Arch Ribs Hoisting and Installation for Xijiang River Bridge on Nanning-Guangzhou Railway

作　　者：袁建新 

机构地区：[1]中铁大桥科学研究院有限公司,湖北武汉430034 [2]桥梁结构健康与安全国家重点实验室,湖北武汉430034

出　　处：《世界桥梁》2016年第1期55-59,共5页World Bridges

摘　　要：为研究南广铁路西江特大桥主桥拱肋吊装过程中结构受力状态,指导拱肋吊装施工,对拱肋吊装施工过程进行仿真分析。该桥主桥为主跨450m的钢箱提篮拱桥,拱肋采用斜拉扣挂悬拼法施工,利用MIDAS软件建立整个拱肋有限元计算模型,采用"合理位移内力法"确定扣锚索初拉索力,对不同拆除过程中结构内力及位移变化的过程进行计算并确定拆除顺序,根据确定的扣锚索初拉索力以及拆索顺序计算出整个吊装过程的主体结构及临时设施的内力及位移。计算及实践结果表明:拱肋悬臂拼装过程中扣塔塔偏和应力以及主拱内力均满足规范要求;从跨中对称向拱脚方向拆除扣锚索的顺序为最优顺序,拆除过程中结构内力及位移变化过程平缓,无突变现象。实践表明,仿真分析结果顺利地指导了现场施工,大桥钢箱拱肋高精度合龙,吊装过程中结构施工处于安全状态。To study the load bearing condition of the structure during the arch ribs hoisting and installation process of the main bridge of the Xijiang River Bridge on Nanning-Guangzhou Railway and guide the construction of the arch ribs,the construction process of the arch ribs hoisting and installation was simulated and analyzed.The main bridge of the Bridge is a steel box basket handle arch bridge with a main span of 450 m,with the arch ribs constructed by cantilever assembly method assisted by fastening cables.The MIDAS software was used to establish the finite element calculation model of the overall arch ribs,and the＂rational displacement internal force method＂was used to determine the initial tensioning force of the fastening cables,and the internal force and displacement of the structure during different dismantling processes were calculated to determine the dismantling sequence.According to the initial tensioning force of the fastening cables and the dismantling sequence of the fastening cables,the internal force and displacement of the main structure and temporary facilities during the overall hoisting and installation process were worked out.The calculated results and the actual engineering practice demonstrate that the offsetting and stress of the fastening towers and the internal force of the main arch ribs during the cantilever assembling process of the arch ribs meet the code requirements.The ideal fastening cable dismantling sequence is to start from the midspan and symmetrically proceed towards the arch springs.During the dismantling process,the variation of the internal force and displacement of the structure was smooth,and no abrupt changes were observed.The results of the simulation calculation successfully guided the field construction,and the steel box arch ribs of the bridge was closed with high precision,and the construction of the structure during the hoisting and installation process was in safe condition.

关 键 词：提篮拱桥 拱肋 吊装 扣锚索 索力 位移 应力 内力 仿真分析 有限元法 

分 类 号：U445.4[建筑科学—桥梁与隧道工程]