【作者】 吴振；

【导师】 龙跃；

【作者基本信息】 广西工学院 ， 结构工程， 2011， 硕士

【摘要】 斜拉桥是近些年来发展较快的一种桥型结构,在国内外已得到广泛的推广和应用。作为其主要承重构件的斜拉索,其病害问题严重影响着桥梁的正常使用,因此,斜拉索专业养护技术方面需要更深入的研究,认识产生这些病害的原因才能够采取行之有效的应对措施,才能更好的保证拉索的安全性、耐久性和可靠性。本文主要研究目前斜拉桥较常用的平行钢丝拉索和钢绞线拉索的病害产生机理以及针对拉索病害的检测方法;系统全面的介绍两种拉索的构造,总结出两种拉索防护构造的薄弱区,并对防护薄弱区常见病害进行分类探讨;对两种拉索体系的结构特性进行比较分析;结合两种拉索检测的实际工程案例分析拉索的病害病因;并对预应力筋的腐蚀情况进行深入研究,模拟预应力筋的腐蚀环境,在不同应力状态下对预应力筋进行均匀腐蚀,对腐蚀后的预应力筋进行静力拉伸和疲劳试验,探究拉索腐蚀后的力学退化规律。本文通过对两种拉索体系的病害研究,提出了一些拉索设计和施工上的改进措施,以及给出斜拉索专业养护的方法和建议;两种拉索体系的比较也可为拉索的选用提供参考;通过模拟实验得知,拉索用预应力筋在应力状态下腐蚀速度剧增,腐蚀后的预应力筋力学性能退化明显,特别是其抗疲劳能力严重下降。更多还原

【Abstract】 In recent years cable-stayed bridge is a kind of bridge structure which is rapid development at home and abroad, has been widely popularized and applied. Stay cables as its main mechanical structure component, their diseases problems directly influence the safety and serviceability of bridge. So therefore, professional maintenance technology of stay cabls need in-depth research, we have to know the reasons of the diseases and could take effective measures to ensure the lasso safety, durability and reliability.This paper primarily makes a study of the diseases occurring mechanism of the more commonly used parallel wire cable and steel strand of the cable-stayed ,and detection methods of lasso disease. Introduce the two cables’structure systematically and comprehensively, summarize the weak area of the two lasso protective structures, and classify the common diseases in the protective weak area .compare and analyse the features of two lasso system structure,and study their reasons of damage based on the actual projects. The more depth reserch are used in corrosion of steel wire strands. By the steel wire strands accelerated in different stress conditions corrosive experiment, static tensile experiments and fatigue test , to study the mechanical properties of degradation degree.Based on studying the diseases occurred in lasso’design, production,construction, maintenance and so on, From the research of lasso’system disease,some measures can be put forward on stay-cables’design and production for improvement, and given stay-cables professional maintenance methods and suggestions; The comparison of the two lasso systems also can be used for reference of the cable-stayed selection. From the experiment ,we could realize that steel wire strands’corrosion rate increse heavily in stress state, the mechanical property of corrosive strands degenerate obviously,especially its anti-fatigue capability decline seriously.更多还原