虚拟横梁单元法在小箱梁桥建模中的应用

Application of virtual beam element method in small box-girder bridge model building

本文以由4片分体式组合箱梁组成的40m单跨简支梁桥为研究对象,利用大型有限元软件MIDAS/Civil,分别建立了实体单元模型、虚拟横梁单元模型,对比分析了2种计算模型在4种荷载工况下各片箱梁的跨中位移解。计算结果表明:实体模型计算结果准确但建模复杂,与之相比,虚拟横梁单元模型的最大误差为-2.3%。得出了虚拟横梁单元法是分体式组合小箱梁桥的合适建模方法,可用于分体式组合小箱梁桥结构分析。

In this paper, by the combination of four separate components of the 40m box girder single- span simply supported girder bridge as the research object, The solid element model and the virtual beam element model of the bridge are established by using the finite element software MIDAS/Civil, Every beam crossdisplacement of the two calculation models in four kinds of load condition are compared. The results show that the solid element model are accurate but modeling complex, the virtual beam element model has the maximum error about - 2.3% compared with the solid model. The appropriate spatial FEM model building method has been found which is the proved virtual beam element model method. Conclusion of the study can be directly applied to the separated small box girder bridge＇s calculation and analysis.