Evaluation of Holding Strength of Existing Steel Bridges and Development of Health Monitoring System Based on It.

今年是本项目的最后一年，现将本年度的研究成果总结如下。(1)在互联网上开放损害案件实例数据库。包括对其产生原因的评价、修复方法及其效果。还开发了更新该数据库的系统，以增加国内外调查人员关于损害赔偿的最新资料。(2)开发了动态称重系统，用于自动测量既有桥梁上车辆的车轴重。在这一年里，为了提高系统的精度，引入了基于两个不同位置应变数据的车辆速度测量系统。(3)为了研究温度变化对钢桥变形特性的影响，对混凝土板梁试件的冷却过程进行了性能观察。在试验中，将钢梁试件加热到一定温度，然后打开空气冷却。在本研究中，考虑了钢与混凝土之间的热容量差异的影响，以及鞋部支承条件（固定或自由）的差异的影响。除试验结果外，结合试件有限元分析结果，探讨了温度变形在桥梁监测中的应用可能性。(4)建立了钢桥整体结构体系有限元分析模型，确定了钢桥上部结构和桥墩的整体结构体系。它的建造没有考虑设计中的一些假设，而是考虑了桥梁的实际结构。(2)中实测荷载的分析结果与桥梁的实际性能吻合较好。(5)利用去年开发的利用光纤网络的实时远程监测系统，利用上述(2)和(4)的系统，建立了钢桥健康与损伤监测系统，目前该系统已长期使用。少

This year was the final year of this project, and the summary of the research results of this year is as follows.(1) The database of the examples of damage cases was opened on Internet. It includes the evaluation of the causes of them and the repairing methods with their effects. The system for updating this database was also developed to add the latest information on damages from the domestic and overseas investigators.(2) The system for Weigh-in-Motion was developed to measure the axle weight of vehicles on existing bridges automatically. In this year, the improvements of the system were done to make the accuracy better by introducing the measuring system of the velocity of vehicles from the strain data at two different positions.(3) In order to investigate the influence of the change of temperature on the deformation characteristics of steel bridges, the observation of the behavior during cooling process of a girder specimen with concrete slab were carried out. In the tests, the who … More le girder specimen was warmed up to some temperature, and then it was opened to the air to be made cool. In this study, the influence of the difference of heat capacity between steel and concrete, and the influence of the difference of the supporting condition (fix or free) at the shoe were considered. In addition to the testing results, with considering the results of FEM analysis of the specimen, the possibility of the application of deformation due to temperature to bridge monitoring was discussed.(4) The FEM analysis model was built to identify the structure system of the whole of a steel bridge including the superstructure and piers. It was built without considering some assumptions in design, but with considering the actual configuration of the bridge. The resu lts of the analysis with the load measured in (2) applied showed good agreements with the actual behavior of the bridge.(5) With the system of real-time remote monitoring system utilizing optical fiber network that was developed by the last year, by using the system above-mentioned in (2) and (4), the system to monitor health and damage of steel bridge was built, and in present, the system is in long term use. Less