中文摘要：

以在建城市轨道交通高架桥为研究背景,分别建立了平面杆系和空间有限元模型,对不对称U型梁的空间受力行为进行了有限元分析,研究了U型梁在主力荷载、附加力荷载等作用下的结构变形和应力分布情况。结果表明,不对称U型梁具有明显的空间受力特征,不满足＂平截面假定＂,底板横向应力的影响不可忽略,结构设计时需要考虑构造措施。

英文摘要：

Based on an urban rail transit viaduct under constructing,the plane frame model and space finite element model were established respectively to analyze the special force behavior of asymmetry U-shaped girder. The structural deformation and stress distribution of U-shaped girder under active load and subsidiary load were also studied. The results showthat the asymmetry U-shaped girder has obvious spatial force characteristics,which does not satisfy the plane section assumption. The effect oflateral stress at the bottom of the U-shaped girder cannot be ignored and the structural measurement should be taken into account in structure design.