窄幅钢箱连续组合梁受力性能有限元分析

Finite Element Analysis on Force Performances of Narrow Steel Box Continuous Composite Beams

为了解决钢-混凝土组合梁负弯矩区开裂以及钢箱受压屈曲问题,提出采用窄幅钢箱连续组合梁对钢-混凝土组合梁进行优化,并在窄幅钢箱连续组合梁桥面翼板的负弯矩区采用超高性能混凝土材料部分替代强度等级为C40的混凝土,形成超高性能混凝土-窄幅钢箱连续组合梁,进一步优化窄幅钢箱连续组合梁受力性能;采用有限元分析软件ABAQUS建立超高性能混凝土-窄幅钢箱连续组合梁有限元模型,在验证模型适用性的基础上,分析窄幅钢箱连续组合梁的受弯过程,并对窄幅钢箱连续组合梁翼板、钢筋、钢箱云图进行对比。结果表明:窄幅钢箱连续组合梁中混凝土的充填跨度对窄幅钢箱连续组合梁刚度存在一定的影响,超高性能混凝土材料显著改善了翼板的抗裂性能,翼板受拉区损伤面积减小95%以上;当采用超高性能混凝土材料完全替代普通混凝土材料时,窄幅钢箱连续组合梁的刚度、开裂荷载、极限荷载等性能得到较大改善。

To solve the problems of cracking in negative moment zones and buckling of steel boxes under compression in steel-concrete composite beams,it was proposed to optimize the steel-concrete composite beams by using narrow steel box continuous composite beams.Ultrahigh performance concrete materials were used to partially replace the concrete with strength grade C40 in the negative moment zones of bridge deck flanges in the narrow steel box continuous composite beams,forming ultrahigh performance concrete-narrow steel box continuous composite beams to further optimize force performances of the narrow steel box continuous composite beams.A finite element model of the ultrahigh performance c oncrete-narrow steel box continuous composite be ams was established by using finite element analysis software ABAQUS.On the basis of verifying applicability of the model,bending process of the narrow steel box continuous composite beams was analyzed,and flanges,reinforcement and steel box clouds of the narrow steel box continuous composite beams were compared.The results show that the filling span of concrete in the narrow steel box continuous composite beams has a certain in fluence on the stiffness of the narrow steel box continuous composite beams.The cracking resistance of the flanges is significantly improved by the ultrahigh performa nce concrete materials,and the damage area in tension zones of the flanges is reduced by more than 95%.The stiffness,cracking load,and ultimate load of the narrow steel box continuous composite beams are greatly improved when the ordinary concrete materials are completely replaced by the ultrahigh performance concrete materials.