基于刚度相似原理的斜拉桥模型设计方法

模型试验是测定结构性能进行科学研究的重要手段之一,目前关于斜拉桥模型设计方法的系统研究还很少。本文提出了斜拉桥模型设计的总体思路,对结构静动力模型的相似关系进行了推导,并完全按照相似关系设计了一座三跨PC斜拉桥的理想模型桥,将其与实桥有限元数值模拟及原型成桥现场静动力测试结果进行比较分析。结果表明,对于斜拉桥这种组合体系结构,当存在两种弹性模量相似比时,采用刚度相似法处理相似关系是合理的。最后,阐述了实际中制作斜拉桥模型时应考虑的问题,为斜拉桥模型的设计制作提供指导。

Design Method of Small-scale Cable-stayed Bridge Based on Stiffness Similarity Theory

Model test is one of the important means for evaluating structure performance. Currently, there are only a few researches about design method of small-scale cable-stayed bridge. General idea for small-scale cable-stayed bridge design method is presented in this paper, and similarity relation for static and dynamic model is derived. According to similarity relation, a three-span prestressed concrete small-scale cable-stayed bridge was virtually built, and comparison was made among the model and prototype numerical analysis and prototype field static and dynamic test results. Results show that for cable-stayed bridge that is one kind of combined structure, stiffness similarity method is suitable when there are two different elastic modulus similarity ratios. Finally, important problems concerned in small-scale cable-stayed bridge design are discussed to provide guidance for small-scale cable-stayed bridge design.