三塔斜拉桥悬臂施工阶段分离式钢箱梁剪力滞效应分析  

Shear Lag Effect Analysis of Separate Steel Box Girder in Cantilever Construction Phase of Three-Tower Cable-Stayed Bridge

作　　者：李丰成 刘建 LI Fengcheng;LIU Jian

机构地区：[1]长沙理工大学土木工程学院,湖南长沙410114

出　　处：《重庆建筑》2025年第2期83-88,共6页Chongqing Architecture

摘　　要：为研究三塔斜拉桥悬臂施工状态下超宽幅分离式钢箱梁引起的纵桥向正应力沿横向截面分布规律,依托某三塔斜拉桥工程实例,利用ABAQUS软件建立分离式钢箱梁空间有限元模型,考虑了悬臂状态下不同梁段长度、最大悬臂以及合龙阶段的典型荷载工况,采用有限元法研究分离式钢箱梁斜拉索锚固截面、横梁联结截面和无横梁联结截面的剪力滞效应。通过与实测值的比较验证了有限元模型的准确性,并计算分析得出在不同荷载工况下剪力滞效应在分离式钢箱梁顶板和底板的分布规律。研究表明,在悬臂施工阶段不同梁段长度、顶板和底板的剪力滞系数沿横向分布规律有一定的差异,随着各阶段荷载条件和位移边界条件的变化,剪力滞效应呈减弱的趋势;斜拉索锚固截面的剪力滞效应比其他两类截面更为突出;与合龙阶段相比,悬臂施工阶段的剪力滞效应更应引起重视。To study the longitudinal stress distribution along the crosssection of a super-wide separate steel box girder caused by shear lag effect during the cantilever construction of a three-tower cable-stayed bridge,this paper uses a real-world engineering case to establish a spatial finite element model of the separate steel box girder using ABAQUS software.The study considers typical load conditions in the cantilever state,including different beam segment lengths,maximum cantilever,and closure stages.The finite element method is used to study the shear lag effect in the anchoring sections of the cable-stayed cables,transverse beam connection sections,and non-transverse beam connection sections.By comparing with measured values,the accuracy of the finite element model is validated,and the shear lag effect distribution in the top and bottom plates of the separate steel box girder under different load conditions is calculated and analyzed.The results show that the shear lag effect differs across beam segment lengths,and the shear lag coefficient varies along the transverse distribution of the top and bottom plates.With changes in load conditions and displacement boundary conditions,the shear lag effect tends to weaken.The shear lag effect in the cable anchoring section is more pronounced than in the other two sections.Compared with the closure stage,the shear lag effect during the cantilever construction phase should be given more attention.

关 键 词：斜拉桥 超宽幅钢箱梁 悬臂施工 剪力滞效应 有限元分析 

分 类 号：U448.27[建筑科学—桥梁与隧道工程]