作　　者： ; ; ; ; ; (田海）; (孙绪东）;

机构地区： 同济大学土木工程学院土木工程防灾国家重点实验室

出　　处： 《建筑结构学报》 2014年第10期10-20,共11页

摘　　要： 为研究钢-混凝土组合梁在负弯矩作用下的畸变屈曲问题,基于作者在前期的试验研究,建立组合梁非线性有限元分析模型,其有效性得到试验数据的验证。应用该有限元分析模型进一步分析了端部弯矩比、力比、腹板高厚比、H形钢截面高宽比、受压翼缘侧向长细比、残余应力分布模式、组合程度等7种参数对组合梁畸变屈曲及受弯承载力的影响。分析结果表明:随着端部弯矩比、腹板高厚比、受压翼缘侧向长细比增大,受弯承载力减小。随着力比增大,受弯承载力增大。焊接截面组合梁的受弯承载力小于轧制组合梁的受弯承载力。组合程度对受弯承载力的影响较小。提出考虑上述影响参数以及侧向弯曲屈曲和侧向弯扭屈曲两种失稳模式的受弯承载力计算公式,计算结果与有限元分析以及试验结果吻合较好。 To investigate the distortional buckling of steel-concrete composite beams subjected to negative bending moment,nonlinear finite element modeling of composite beams was developed on the basis of the authors' previous experiments and its validity was verified by the experimental findings. Using this modeling,the effects of seven parameters,such as bending moment ratio between two ends of a beam,force ratio,height-to-width ratio of H-section steel,height-to-thickness ratio of web,lateral slenderness ratio of compressive flange,pattern of residual stress distribution,composite level,on the bending capacity of a composite beam due to distortional buckling were analyzed.It is found from the FEA that bending capacity decreases as the bending moment ratio between two ends of a beam,height-to-thickness ratio of web and lateral slenderness ratio of compressive flange increase respectively. Bending capacity increases as the force ratio increases. Bending capacity of the composite beam with welded H-shaped cross section is less than bending capacity of the composite beam with hot rolled H-shaped cross section. The composite level has nothing to do with bending capacity. Formulas for calculating the bending capacity bending capacity were proposed which considers the above-mentioned influence parameters and two kinds of instable modes including lateral bending buckling and lateral bending-distortional buckling. The result obtained from the formulas agrees well with that from the FE analysis as well as that from the experiments.

关 键 词： 钢 混凝土组合梁 畸变屈曲 受弯承载力 有限元分析 建议公式

领　　域： [建筑科学]