典型人字形桥梁模型试验研究与分析

ANALYSIS AND STUDY ON MODEL EXPERIMENT OF TYPICAL Y-SHAPE BRIDGE

为分析受力复杂的异形薄壁箱梁桥,在初等梁理论的基础上,通过增加自由度的方法,提出每个节点10个自由度的薄壁箱梁分析单元。同时从现有的人字形桥梁中抽象出一种典型的结构作为研究对象,根据相似理论建立有机玻璃模型,设置了多种支座形式及多种荷载工况下的试验测点。另外,分别建立初等空间梁格与板壳有限元模型,同时对模型的理论分析与实测结果进行比较。研究结果显示初等梁理论不能较好地反映人字形薄壁箱梁桥的受力行为,并指出板壳理论在结构整体分析时尚存在不足,验证了该文理论分析方法的正确性和简便性,为求解人字形桥梁复杂受力行为提供了一种有效的途径。

In order to solve the complex mechanical problem of thin-walled box girder of Y-shape bridge, the authors proposed a spatial finite element with 10 degrees of freedom for every node of the thin-walled box girder by increasing the degrees of freedom based on the theory of elementary beam. Meanwhile, the authors selected a typical Y-shape bridge from existing Y-shape bridges as a model example, the organic glass model of the typical Y-shape bridge was built according to the similarity theory. Monitoring points were placed on the experiment model with different supports and under different loading cases. In addition, the authors built the model of a spatial shell and the model of an elementary beam, and compared the results of the theoretical analysis with the experimental results. The analytical results show that the theory of elementary beam can not reflect the mechanical behaviors of the structure exactly, and the theory of shell has substantial weakness in the analysis of the whole structure, the result also indicates that this paper＇s method is correct and simple. The research results provide a new method to solve the problem.