A Study on Life-Prediction and Life-Expansion of Existing Steel Bridge

既有钢桥寿命预测及延寿研究

基本信息

批准号：
07455182
负责人：
MIKI Chitoshi
金额：
$ 4.42万
依托单位：
Tokyo Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1997
项目状态：
已结题

项目摘要

Recently, it has been often reported that fatigue failure occurred in many steel highway and railway bridges. From this background, now it becomes much important to estimate the way to predict of life of bridge and to make an efficient plan of maintenance work. In this study, aiming to establish the way of life prediction and life-expansion of steel bridges, the following studies were carried out considering fatigue.1) In order to predict life of existing bridges, it is very important to know location, type, and reason of fatigue crack in Existing bridge. First, in this study, to establish the data-base, fatigue failure occurred in steel highway and railway bridge in Japan and U. S. A were rearranged2) Next, in order to discuss the mechanism of occurrence of fatigue failure, stress measurement and FEM analysis were carried out. Here, scallop detail and cross-connection detail were studied in testing laboratory and also actual bridges considering secondary stress and deformation mode.3) Finally, aiming life-expansion of steel bridges, some fatigue improvement methods were studied with using small welded joint specimens (such as out-of-plane gusset welded joint, in-plane gusset welded joint and cruciform welded joint) and girder specimen including some welded joints (such as web gusset, flange gusset and vertical stiffener). As fatigue strength improvement method, under-matching weld electrode and post-welding processing at welded toe such as TIG-dressing, burr-grinding and hammer peening were dealt with in this study.

最近，经常据报道，许多钢制高速公路和铁路桥梁发生疲劳失败。从这种背景来看，估计预测桥梁生活并制定有效维护工作计划的方式变得非常重要。在这项研究中，旨在建立钢桥的生活方式预测和生命扩张，考虑了以下研究考虑疲劳。1）为了预测现有桥梁的生命，了解现有桥梁中疲劳的位置，类型和疲劳的理由非常重要。首先，在这项研究中，为了建立数据库，在日本和美国的铁路桥上发生疲劳失败。 Here, scallop detail and cross-connection detail were studied in testing laboratory and also actual bridges considering secondary stress and deformation mode.3) Finally, aiming life-expansion of steel bridges, some fatigue improvement methods were studied with using small welded joint specimens (such as out-of-plane gusset welded joint, in-plane gusset welded joint and cruciform welded joint) and girder标本包括一些焊接接头（例如Web Gusset，法兰角和垂直加强剂）。作为疲劳强度改善方法，在这项研究中处理了焊接脚趾的匹配焊接电极和焊接后处理，例如Tig-Dressing，Burr-Grinding和Hammer Peening。