自锚式悬索桥

本文介绍了自锚式悬索桥的特点,国外自锚式悬索桥的发展历史和已建成的自锚式悬索桥的情况;介绍了国内自锚式悬索桥方面的设计、施工经验,并对该桥型的发展、应用前景进行了分析。     

一座自锚式悬索桥的设计

通过对某自锚式悬索桥概况及技术标准的介绍,阐述了该悬索桥的受力特性及设计要点,并对其施工技术要点作了分析,从而为类似条件下的单塔混凝土自锚式悬索桥的设计与施工积累经验.     

大跨径小矢跨比人行悬索桥力学性能分析研究

人行悬索桥相比公路悬索桥而言,桥面宽度较窄,结构整体刚度小,属于大跨径柔性结构。国内外大多数悬索桥的矢跨比都在1/12～1/9之间,人行悬索桥考虑到景观效果要求,因此可能设计成小矢跨比悬索桥。为了研究小矢跨比人行悬索桥的受力性能,该文以1/16小矢跨比景区大跨径人行悬索桥为研究对象,通过美国大型通用高级非线性有限元软件MSC.Marc建立了主跨416m人行悬索桥三维空间有限元分析模型,研究了小矢跨比下人行悬索桥结构受力性能。分析结果表明,小矢跨比人行悬索桥在一定程度上影响结构整体刚度的变化,得出在不同荷载作用效应下结构受力性能规律,并且在景区修建小矢跨比人行悬索桥是可行的,研究结论可为柔性人行悬索桥的合理设计提供一定参考依据。     

自锚式悬索桥

本文介绍了自锚式悬索桥的特点，国外自锚式悬索桥的发展历史和已建成的自锚式悬索桥的情况；介绍了国内自锚式悬索桥方面的设计、施工经验，并对该桥型的发展、应用前景进行了分析．     

悬索桥主缆线形计算和绘图实用方法

以悬索桥设计为研究对象,介绍了悬索桥主缆中跨与边跨悬链线的理论公式,并阐述了悬索桥主缆线形的计算及绘图方法,指出实际工程中,在吊索集中荷载作用下,主缆线形会发生变化,为防止变形过大,设计应考虑主缆的重力刚度要求。     

悬索桥的检测及维修方法研究

针对悬索桥检测维修工作的必要性,以桥梁维修理论为基础,在总结有关桥梁的检测、维修方法的基础上,对某悬索桥的检测工作及维修方案做了介绍,以期进一步完善悬索桥的设计理论.     

大跨度人行悬索桥结构设计关键技术

结合现有景区人行悬索桥的研究和建设情况,首先介绍景区人行悬索桥的特点及应用,其次介绍人行悬索桥的结构分类及受力特点,分别从荷载取值、缆索选用、找形分析、人致振动问题、节点设计和桥面板设计六个方面对人行悬索桥设计的关键技术问题提出归纳和建议.结果表明:主缆和抗风缆可按顺序分别找形,避免同时调整两类缆索;现有规范考虑到的自振频率区间未包含实际频率,已不能满足大跨度人行悬索桥设计的需要,应对大跨度人行悬索桥的频率敏感范围进行研究;吊索与主缆及桥面的连接节点是当前设计中常被忽略的薄弱环节,应根据索内力和应力幅进行节点设计和疲劳验算;最后给出了玻璃桥面板设计的5项建议.     

某悬索桥隧道锚防排水设计及施工技术

基于某悬索桥隧道式锚碇的结构类型、受力特点,对悬索桥隧道锚工程进行防排水设计与施工。介绍了悬索桥隧道锚的防排水设计原则及构造特点,详细阐述了隧道锚防水工程的材料要求、施工工艺、质量检测及缺陷处理。     

铁路悬索桥的刚度问题探讨性研究

对铁路悬索桥较为合理实用的刚度指标体系做了调研分析,并按照建议的刚度指标,对悬索桥的边中跨比、垂跨比、高跨比、宽跨比等参数做了对比分析,总结提出了适合铁路悬索桥的一些设计参数,最后简单介绍了不同结构体系悬索桥对结构刚度的贡献及存在的问题,以供参考借鉴。     

自锚式悬索桥合理成桥状态设计方法分析

通过对自锚式悬索桥的结构体系特性、施工工艺特点、结构设计流程以及基于有限位移理论的分析,从自锚式悬索桥主缆线形计算的基本理论出发,以得到主缆合理成桥状态入手,提出了确定自锚式悬索桥合理成桥状态两阶段设计的思路和方法。并结合工程实例,按照两阶段设计流程,使得大跨径自锚式悬索桥设计目标明确,计算简便快捷,可控性强。     

混合式桥型对超长跨桥梁的适应性

本文对中跨为2500m的混合型斜拉悬索桥的进行了初步设计,构想了三种斜拉悬索桥和一种悬索桥桥式。从初步设计结果中比较它们上部结构钢材的重量发现,考虑到下部结构尺寸,斜拉悬索桥相对悬索桥具有优越性。另外,对这几种型式的桥梁进行了抗弯稳定性分析以及耦合颤振分析。分析结果表明,斜拉悬索桥抗弯稳定性是足够的,而且其临界风速高于悬索桥的临界风速。所以,作者认为针对超长跨度桥梁混合型斜拉悬索桥赛过悬索桥     

System reliability of suspension bridges

Provisions for the design of existing suspension bridges often rely on a deterministic basis. Consequently, the reliability of these bridges cannot be assessed if current provisions are applied. In order to develop cost-effective design and maintenance strategies for suspension bridges a system reliability-based approach has to be used. This is accomplished by a probabilistic finite element geometrically nonlinear analysis approach. This study forms part of an investigation into the system reliability evaluation of geometrically nonlinear large span bridges recently undertaken at the University of Colorado. A brief review of reliability analysis of geometrically nonlinear elastic structures allows for the determination of its relevance to the assessment of suspension bridges. A probabilistic finite element geometrically nonlinear elastic code is used for system reliability evaluation of suspension structures. The allowable stress design procedures used by the Honshu Shikoku Bridge Authority for the design of suspension bridges are presented along with their application to the design of an existing bridge. This bridge is studied from a system reliability viewpoint to evaluate its reliability under different loading and damage scenarios. Such information calls attention to the fact that the reliability of cables, hanger ropes and girders are very different. Therefore, optimal maintenance decisions for suspension bridges designed according to allowable stress method are not consistent with those based on equal component reliability values.     

辅助结构对悬索桥的颤振稳定性的影响

随着悬索桥跨度不断增加,风荷载引起的稳定性问题在悬索桥的设计过程中的地位越来越重要,探求具有优异结构性能的悬索桥结构形式成为一项极有意义的工作,本文旨在研究在传统悬索桥基础上增加辅助结构之后悬索桥自振特性的变化,并寻求提高悬索桥颤振临界风速的有效措施。     

State-of-the-art of long-span bridge engineering in China

This paper introduces the state-of-the-art of longspan bridge engineering in China with emphases on recent long-span bridge projects, bridge deck configuration and material, design codes of long-span bridges and improvement of aerodynamic performance. The recent long-span bridge projects include thirty-eight completed suspension bridges, cable-stayed and arch bridges with a main span over 400 m, and eighteen major bridges are under construction. The bridge deck configuration and material, with prestressed concrete decks, steel-concrete composite decks and steel box decks together with several popular cross-sections, are presented. The third part briefly outlines four design codes, including static and dynamic design for highway long-span bridges, and the recent engineering experiences gained from several aerodynamic vibration control projects of long-span bridges are shared in the last part.     

Investigation of Live Load Deflection Limit for Steel Cable Stayed and Suspension Bridges

Long span bridges such as steel cable stayed and suspension bridges are usually more flexible than short to medium span bridges and expected to have large deformations. Deflections due to live load for long span bridges are important since it controls the overall heights of the bridge for securing the clearance under the bridge and serviceability for securing the comfort of passengers or pedestrians. In case of sea-crossing bridges, the clearance of bridges is determined considering the height of the ship master from the surface of the water, the trim of the ship, the psychological free space, the tide height, and live load deflection. In the design of bridges, live load deflection is limited to a certain value to minimize the vibrations. However, there are not much studies that consider the live load deflection and its effects for long span bridges. The purpose of this study is to investigate the suitability of live load deflection limit and its actual effects on serviceability of bridges for steel cable-stayed and suspension bridges. Analytical study is performed to calculate the natural frequencies and deflections by design live load. Results are compared with various design limits and related studies by Barker et al. (2011) and Saadeghvaziri et al. (2012). Two long span bridges are selected for the case study, Yi Sun-Sin grand bridge (suspension bridge, main span length?=?1545 m) and Young-Hung grand bridge (cable stayed bridge, main span length?=?240 m). Long-term measured deflection data by GNSS system are collected from Yi Sun-Sin grand bridge and compared with the theoretical values. Probability of exceedance against various deflection limits are calculated from probability distribution of 10-min maximum deflection. The results of the study on the limitation of live load deflection are expected to be useful reference for the design, the proper planning and deflection review of the long span bridges around the world.     

大跨度自锚式悬索桥的动力特性分析

以钱江九桥和青岛海湾桥大沽河航道桥两座自锚式悬索桥为例,用通用有限元软件ANSYS建立了大桥的三维有限元动力计算模型,对大桥进行了静力和动力计算分析,发现存在多阶拉索振动振型并对此现象进行了分析,为大跨度自锚式悬索桥的设计、施工提供了参考。     

独塔自锚式悬索桥设计

中小跨径的自锚式悬索桥造型优美,是城市桥梁的可选桥型之一。通过一座独塔自锚式悬索桥的方案选择及结构分析,介绍了具体的设计方法。     

悬索桥基准索股的空缆状态

本文首先分析了影响悬索桥主缆线形的各种因素,然后采用精确的悬索桥缆索系统分析程序,对两座典型悬索桥的主缆线形进行了计算分析,比较了成缆空缆状态与基准索股空缆状态,得出了一些有意义的结论,供设计和施工时参考。     

主缆矢跨比对大跨悬索桥经济技术指标的影响

对一跨径为328 m 1138 m 400 m单跨悬索桥的矢跨比为1/9,1/9.5,1/10时的经济技术指标进行了计算和讨论,并结合国内外已建悬索桥的设计实例,以期在技术指标和经济指标间找到一个合理的平衡点,为广大桥梁设计工作者提供了参考。