斜拉桥悬臂施工阶段分离式钢箱梁的剪力滞效应分析

以荆岳长江公路大桥为研究背景,采用ANSYS软件建立了该斜拉桥主梁最大单悬臂、主梁最大双悬臂和悬臂施工2号梁段三个工况的分离式钢箱主梁的区段仿真模型.利用空间有限元法,针对悬臂施工状态下分离式钢箱的空间受力状态进行剪力滞效应的计算分析.研究结果表明,分离式钢箱梁在不同施工工况下,其顶、底板剪力滞系数分布规律不同;钢箱梁顶板在外腹板处剪力滞效应较大,并随着离开外腹板处,其剪力滞效应减小较快.在施工过程中,分离式钢箱主梁的同一截面会同时出现正、负剪力滞效应.

The shear lag effect research of separated steel box girder in cantilever construction stage of cable-stayed bridge

Using the ANSYS software and the Jing Yue Chang-jiang river highway bridge as the research background,this paper sets up the separated steel box girders’ shell element model of three working conditions: the biggest single cantilever,the biggest double cantilever and the second beam assembled completely.Using the spatial finite element method to analyze the shear lag effect of the separated steel box girder in cantilever construction stage,under different conditions,the distribution regularity of separated steel box girder’s shear lag coefficient appears different.The shear lag effect of steel box girder’s top tray is quite serious in the outer web,but the shear lag coefficient decreases faster along the box girder width direction when it leaves the outer web.In the construction process,the positive shear lag effect and negative shear lag effect simultaneously appear in the separated steel box girder.