基于异步悬臂浇筑的波形钢腹板组合梁桥腹板先行架设研究
Research on Erecting Corrugated Steel Webs Ahead of and Asynchronous with Cantilever Casting of Concrete Girders
奉思东 1贺君 1郭宝君 2甘波 3李春跃2
作者信息
- 1. 长沙理工大学土木工程学院,湖南 长沙 410114
- 2. 北京建工土木工程有限公司,北京 100015
- 3. 湖州市城市规划设计研究院,浙江 湖州 313000
- 折叠
摘要
达摩沟大桥主桥为主跨 105 m的双幅波形钢腹板预应力混凝土组合梁桥,采用异步悬臂浇筑法施工.针对该桥波形钢腹板架设工作面多、人员调度紧张的问题,基于传统异步悬臂浇筑方案,提出在悬臂初期同时架设 2 个节段波形钢腹板的优化方案,并通过先行架设腹板的线形控制分析确定采用优化方案的可行节段范围.为验证优化方案的可行性与适应性,采用有限元软件 Abaqus 建立实体模型模拟其施工过程,对比分析异步悬臂浇筑施工优化前、后结构的受力与变形,并进行实桥应用.结果表明:优化方案下先行架设 2 个节段腹板的可行范围为 2～6 号节段,相邻节段腹板的预拱度最大调整值为 6.4 mm,优化方案对各节段顶板与底板应力、相邻腹板剪应力及变形的影响均较小,且应力计算值均小于规范要求的强度设计值.施工中偏安全考虑仅在右幅 1 号墩 2～4 号节段采用优化方案施工,腹板高程均在可调节范围内,且腹板变形实测值与有限元值吻合良好,证明了优化方案的可行性及适用性.
Abstract
With the main span length reaching 105 m,the main bridge of Damogou Bridge consists of two superstructures of prestressed concrete girders that act compositely with corrugated steel webs.To facilitate the erection of the corrugated steel webs and effectively manage personnel scheduling,it was proposed to simultaneously erect the corrugated steel webs(CSWs)in two girder segments at the early stage of cantilever casting,and to use the controlled geometry of the previously-erected CSWs to determine the girder segments that were the best choices for the method.The construction process was simulated in Abaqus to verify the applicability and efficiency of the proposed method.The load bearing behavior and deformation of the superstructures before and after the modification of the asynchronous pouring construction(APC).The proposed method was applied to a real bridge.The numerical simulation and engineering practice demonstrated that it was proper to erect the girder segments No.2-No.6 by the proposed method,where the CSWs in the exact girder segment and the next two segments would be erected ahead of the cantilever casting of concrete,and the maximum pre-camber of the CSWs in the neighboring segment should be set at 6.4 mm.The modified method would not induce great variation of the stresses in the top and bottom slabs of each segment,shear stresses in and deflections of the adjacent webs,and the calculated stresses were smaller than design strengths suggested in the code.To minimize the safety risk,the proposed method was only applied to the construction of the girder segments No.2-No.4 at pier No.1 in the right superstructure,allowing the elevations of CSWs to be within controllable ranges.The measured deflections of CSWs were consistent with the numerical simulation,proving the feasibility and effectiveness of the proposed method.
关键词
组合梁桥/波形钢腹板/悬臂浇筑法/异步施工/应力/线形/有限元法Key words
composite girder bridge/corrugated steel web/cantilever casting/asynchronous construction/stress/geometry/finite element method引用本文复制引用
基金项目
国家自然科学基金项目(52378127)
国家自然科学基金项目(52211530037)
湖南省自然科学基金项目(2022JJ10049)
出版年
2024
NETL
NSTL
万方数据