摘要
为简化剪力滞效应的计算,将箱梁沿纵向离散为若干根带有附加约束荷载的平行梁条.基于刚度等效和相邻梁条间的变形协调条件,获得了各梁条的约束等效荷载.基于梁单元理论和整体结构的边界条件,分别计算箱梁对应位置梁条的弯曲效应,从而得到箱梁全截面的应力分布.通过与有机玻璃试验模型和数值解的比较,分析了梁条模型的精度.研究表明,梁条模型的应力及竖向挠度值与试验值总体接近,变化规律与数值模型解吻合;试验箱梁的梁条应力值与板壳值最大相差9.84%,梁条模型的腹板竖向挠度较板壳值大7.53%;集中荷载以及均布荷载作用下铁路双室箱梁的梁条应力值以及挠度值分别与实体单元值最大相差10.42%、9.2%;梁条模型的计算结果偏于安全,可以计算箱梁的弯曲效应.
In order to simplify the calculation of the shear lag effect of the box girders,the box girder is longitudinally dispersed into a number of parallel beam strips with additional constrained loads.In view of stiffness equivalence and deformation compatibility conditions between adjacent beams,the constrained equivalent loads of each beam are obtained.In view of the beam element theory and the boundary conditions of the overall structure,the bending effects of the corresponding beam of the box girder are calculated respectively,and the stress distribution of the full section of the box girder is obtained.The accuracy of the beam model is analyzed by comparison with the plexiglass test model and numerical solution.The results show that the stress and vertical deflection values of the beam strip model are generally close to the experimental values,and the variation law is consistent with the numerical model solution.The maximum difference between the stress values of the beam-strip and the plate-shell values is 9.84%,and the vertical deflection of the web of the beam-strip model is 7.53%larger than that of the plate-shell value.The stress values and deflection values of the beam strip of the railway double-chamber box girder under concentrated load and uniform load are respectively compared with the solid element values,and the maximum difference is 10.42%and 9.2%respectively.The beam strip model can calculate the bending effect of box girders and its calculation results are partial to safety.
作者
刘应龙
蔺鹏臻
何志刚
马俊军
孙理想
LIU Yinglong;LIN Pengzhen;HE Zhigang;MA Junjun;SUN Lixiang(College of Civil Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China)
出处
《应用基础与工程科学学报》
EI
CSCD
北大核心
2021年第3期718-728,共11页
Journal of Basic Science and Engineering
基金
国家自然科学基金高铁联合项目(U1934205)
国家自然科学基金面上项目(51878323)
关键词
箱梁
剪力滞效应
简化模型
模型试验
精度分析
box girder
shear lag effect
simplified model
model experiment
precision analysis
