【作者】 李毅；

【导师】 项贻强； 段元锋；

【作者基本信息】 浙江大学 ， 桥梁与隧道工程， 2010， 博士

【摘要】 近年来,随着城市化进程的加快和各类桥梁结构破坏及倒塌事故的增多,开展面向公共安全的城市重要桥梁的健康监测与预警处置技术研究,实现城市桥梁的高性能服役和安全保障的目标,体现了我国经济和社会可持续发展的重大需求,成为了一项迫切而重要的科学与工程任务。城市桥梁集群监测平台是数字城市关于基础设施信息化的重要组成部分,以城市干道桥梁结构为对象,应用现代传感、通讯和网络等信息技术,集健康监测系统与城市桥梁管理系统功能于一体,旨在实现资源共享和信息综合,实现一体化集成和开放的分布式网络监测相结合。它将充分发挥健康监测系统在实时监测数据采集与桥梁管理系统在综合状态评估方面的优势,避免目前单一桥梁监测系统可复制性差、各系统间缺乏沟通与整合、容易形成“信息孤岛”、无法为保障城市干道桥梁整体安全提供有效支持的问题,是城市信息化背景下的一种全新桥梁管理模式。系杆拱桥以其优美的结构造型、良好的受力特点、优越的经济性能,越来越受到桥梁工程界的青睐,被大量运用于现代城市桥梁中。本文基于因地制宜、突出重点的原则,结合杭州市区交通干道桥梁在线安全监控管理系统(二期)工程,提出城市桥梁集群监测平台的建设与分阶段实施框架,开展了基于城市桥梁集群监测平台的系杆拱桥健康监测研究,主要的研究内容及创新成果如下：1.从城市桥梁集群监测平台的定位、设计的原则、系统的架构,实现的技术等方面进行了探索,结合杭州市城市桥梁管理养护中长期规划(2008年—2020年),对城市桥梁集群监测平台的分阶段实施进行了规划。目前已建成的集群监测平台包括杭州市城区交通干道上的跨运河桥3座、高架快速路1座、大型立交桥1座,跨铁路斜拉桥1座、跨钱塘江拱桥1座。整个系统基于网通VPN技术,实现了实时的结构动态反应的监测,为摸索各种类型的桥梁在运营阶段实际受力状况积累了大量宝贵的数据,成为全国首个对不同形式的桥梁实行统一在线监管的城市。2.在城市桥梁集群监测平台下,结合典型桥型系杆拱桥—叶青兜桥,重点展开了以下研究：a.基于已有桥梁健康监测系统研究现状与系杆拱桥的特点,实现了叶青兜桥远程在线健康监测,并结合系统运行1年多的监测数据,提出了相应的数据管理规则,实现了监测数据的单点及连续失效检验；基于监测数据的统计分析,建立了桥梁温度的日变化模式和年变化模式,深入研究了各监测信号与环境温度之间的关联关系,建立了相应的回归模型用以消除温度的影响,从而提高监测指标对结构自身损伤的有效性。b.基于监测数据,通过修正结构模型的建模误差和物理特性误差,提高了分析结果与在线监测结果之间的拟合程度,确立了参考有限元模型及预警指标值,实现了在线预警；完善了系杆拱桥实用的评价指标体系,在考虑各评价元素对桥梁安全性、适用性和耐久性的不同影响上,分别确定各元素的初始权重和评价指标分级标准,结合监测数据及模型分析,实现了桥梁的综合量化评估。c.结合系杆拱桥的结构特点,提出了基于构件关键性和易损性的全寿命维护方法。采用基于刚度的构件重要性分析方法结合敏感性分析确定关键构件,揭示构件在结构中的相对关键性及可能存在的薄弱位置,并结合健康监测系统的数据分析与参考模型的数值分析得到构件的能力需求比作为具体评判结构易损性的指标,在此基础上讨论了构件的危险性排序,为系杆拱桥构件的预测式检测养护提供理论依据。最后,在上述研究的基础上,对城市桥梁集群监测平台所面临的问题和发展的方向进行了探讨。更多还原

【Abstract】 In recent years, with the rapid urbanization process and increased accidents of bridge damage and collapse, the research of bridge health monitoring and early-warning technology for the public safety was been promoted. In order to achieve high performance of urban bridge service and security, this research has meets the requirement of the economic and social sustainable development, and becomes an urgent and important issue of both science and engineering.Urban bridge cluster monitoring system is an important part of the infrastructure informationization in the construction of digital city. Taking urban-traffic-corridor bridges as the study object, the system is applying the modern sensing, communications and information network technology to realize the integration and open-distributed network monitoring, which takes full advantage of the health monitoring system with real-time monitoring data collections and the bridge management system in a comprehensive assessment of bridge safety. It can also avoid the poor reproducibility and the lack of communication and integration with the single-bridge monitoring system, which easily forms the "isolated information island" and is unable to provide effective support for the protection of the urban bridge overall security. It’s a new model of urban bridge maintenance and management with the background of city informationization.Tied arch bridges are commonly constructed and become more and more popular in the modern city, due to its beautiful structural esthetics, excellent capability of mechanics and economical cost-effectiveness. This thesis takes the development of on-line safety monitoring and management system (Phase II) of Hangzhou traffic corridor bridges as the engineering background to promote urban bridge cluster monitoring system development and implementation. The main research contents and innovation achievements are as follows:1. The cluster monitoring system was explored from the aspects of orientation, design principles, system architecture and implementation technology, meanwhile, according to the long-term plan of Hangzhou urban-bridge maintenance and management (2008-2020), the implementation during all the planning stages were discussed. The current monitoring system includes three crossed canal bridges, one elevated freeway, one cable-stayed bridge across the railway and one arch bridge across Qiantang River. The whole system was based on the VPN technology, realized the on-line monitoring of structural dynamic responses, and collected a great deal of valuable data to explore the actual safety state of various types of bridges in the operational phase. Hangzhou became the first city in China which established a unified online monitoring system for different types of bridges.2. Based on the urban bridge cluster monitoring system, the Yeqingdou bridge subsystem was studied focus on the following research contents:a) The online health monitoring subsystem of Yeqingdou Bridge was developed, which combined the characteristics of tied arch bridge with existing research of bridge health monitoring system. Based on the 1 year monitoring data, the corresponding data management rules were set up at first; then the automatic identification methods of single-point and continuous failure data was discussed respectively; finally, according to the statistical analysis of monitoring data, the daily and annual temperature variation patterns have been investigated, the correlation between the monitored structural responses and temperature were revealed, with the regression model. The temperature induced effects were eliminated from the total structural responses and improved the effectiveness of structural damage identification of the monitoring index.b) Based on the monitoring data analysis, the reference finite element model was established by means of updating the modeling error and the physical properties of the bridge structure, which improved the agreement that between the analysis results and the on-line monitoring data, and the thresholds of early warning indicators were calculate to realize the online alarming. According to the Analytic Hierarchy Process, the evaluation index system of tied arch bridge was established with the consideration of different assessment index effects on the bridge safety, serviceability and durability. The initial weights of each element and index assessment criteria were determined by combing the model analysis and monitoring data statistical analysis. Finally, the object of quantitative evaluation to bridge safety was achieved.c) The method of life-cycle maintenance strategy based on the criticality and vulnerability analysis with the consideration of tied arch bridge characters was proposed. Based on component rigidity criterion and sensitity analysis, the criticality components were determined and the relative importance of the structure members or possible schwachstelle was revealed. Meanwhile, by combining the structural theoretical analysis and on-site monitoring data, the capability-demand ratio was computed and the vulnerable bridge components were identified. Finally, the risk sequence of the tied arch bridge components was determined to guide the monitoring and maintenance strategy.In the end, based on the above studies, the problems and future development of the urban bridge cluster monitoring system were discussed.更多还原