组合梁斜拉桥拉索重要性分析及锈蚀影响研究

Analysis of the importance of stay cables and research on the effect of rust in composite beam cabled bridges

组合梁斜拉桥在大跨径桥梁中应用广泛,其主梁刚度相对较弱、混凝土板容易开裂,整体受力状态受斜拉索运营状况的影响较大。为研究斜拉索锈蚀或断索对组合梁斜拉桥的影响程度,给出斜拉索的日常管养建议。依托一座大跨径钢-混组合梁斜拉桥,首先通过基于广义结构刚度的变化率指标对各斜拉索进行构件重要性分析,明确斜拉索的重要性排序关系,得出管养重点关注索区;然后通过有限元软件,模拟了依托工程在管养重点索区内斜拉索锈蚀后的力学状况,得出斜拉索逐步锈蚀劣化对桥梁结构静力效应的影响程度。研究成果为制定该类桥型相应的养护措施提供了参考。

Composite beam cable-stayed bridges are widely used in large-span bridges,with relatively weak main beam stiffness and easy cracking of concrete slabs.The overall stress state is greatly affected by the operation of the cable-stayed cables.To study the impact of corrosion or breakage of stay cables on composite beam cable-stayed bridges and provide daily maintenance suggestions for stay cables.This article relies on a large-span steel-concrete composite beam cable-stayed bridge.Firstly,the component importance of each stay cable is analyzed based on the change rate index of generalized structural stiffness,and the importance ranking relationship of stay cables is clarified,and the key focus of maintenance is identified in the cable area;Then,using finite element software,the mechanical condition of the corroded stay cables in the key cable area of the maintenance project was simulated,and the degree of influence of the gradual corrosion deterioration of the stay cables on the static effect of the bridge structure was obtained.The research results of this article provide a reference for formulating corresponding maintenance measures for this type of bridge.