42m简支多主梁活载组合钢板梁有限元分析

Finite Element Analysis of a 42 m Simply Supported Multibearing Live-load Composite Steel Plate Beam

简支组合钢板梁桥具有构造简单、自重轻、强度高、施工方便等优点,在桥梁建设中有着广泛的应用。当桥梁较宽时,多主梁的布置方式可以充分改善主梁及桥面板的受力从而使构造简化。以某42m简支多主梁活载组合钢板梁为对象,通过大型通用有限元软件MIDASCIVIL分别按照双层单元法、联合截面法、混合单元法建立了有限元模型,对这种组合梁的受力及建模方式进行了比较。结果表明:组合作用下,双层单元法和联合截面法的应力基本一致,二者与混合单元法相比较,钢主梁顶板应力比较接近,底板应力偏大。

It has the advantages of simple structure, light weight, high strength, convenient construction and it is widely used in bridge construction.When the bridge is wide, the arrangement of multi-main beams can fully improve the stress of the main beams and the bridge deck, thus simplifying the structure. In this paper, 42m simple supported multi-bearing live-load composite steel plate beam is used as the object. The finite element models are established by the large general finite element software MIDAS CIVIL according to the two-layer unit method, the joint section method and the mixed element method.The paper analyzes and compares the stress and modeling methods of this composite beam. The results show that the stress of the first two methods is basically the same under combined action. Compared with the mixed element method, the stress of the roof of the steel main beam is close to that of the bottom plate.