注册 登录  
 加关注
   显示下一条  |  关闭
温馨提示!由于新浪微博认证机制调整,您的新浪微博帐号绑定已过期,请重新绑定!立即重新绑定新浪微博》  |  关闭

我的博客

清谈不觉晓:完全原创、自娱自乐

 
 
 

日志

 
 

帕劳(Palao)Koror 桥的倒塌  

2013-03-28 22:04:51|  分类: 桥梁事故 |  标签: |举报 |字号 订阅

  下载LOFTER 我的照片书  |

帕劳(Palao)Koror 桥的倒塌 - liu-xiaoyao - 我的博客
桥位
帕劳(Palao)Koror 桥的倒塌 - liu-xiaoyao - 我的博客
桥梁跨中凹陷1.3米(1977年6月建成)

The original Koror-Babeldaob Bridge was a balanced cantilever prestressed concrete box girder bridge with a mainspan of 240.8 m and total length of 385.6 m (1265 ft). It was designed by Dyckerhoff & Widmann AG and Alfred A. Yee and Associates. It was constructed by Dyckerhoff & Widmann AG, contractor was Palau based Korean company, Socio Construction Co. It was the world's largest bridge of its type, until its record was broken by the 260 m span of the Gateway Bridge in BrisbaneAustralia, finished in 1985.

This led to two studies carried out by Louis Berger International and the Japan international Co-operation Agency. They concluded that the bridge was "safe" and the large deflections were due to creep and the modulus of elasticity of the concrete in place being lower than anticipated.

On September 26, 1996, the bridge suddenly collapsed and shut off fresh water and electricity between the islands. In addition, the collapse killed two people and injured four more. This caused the government to declare a state of emergency. By request of Kuniwo Nakamura, then the country's President and foreign minister, Japan provided emergency aid as well as a temporary bridge.

帕劳(Palao)Koror 桥的倒塌 - liu-xiaoyao - 我的博客
桥梁构造&施工程序
帕劳(Palao)Koror 桥的倒塌 - liu-xiaoyao - 我的博客
原桥预应力和铰 & 纵向体外预应力加固并封铰
(1998年6月加固结束)

The 18-year old, Koror-Babeldaob bridge (KB bridge) collapsed abruptly and catastrophically. The failure occurred during benign weather and loading conditions, less than three years after two independent teams (Louis Berger International and the Japan international Co-operation Agency) of bridge engineers had evaluated the bridge and declared it safe, and less than three months after completion of a strengthening programme to correct a significant midspan sag that was continuing to worsen.

According to British civil engineers Chris Burgoyne and Richard Scantlebury, the reinforcement operation had 4 main components.By 1990, a physical phenomenon called creep had caused the midline of the bridge to sag 1.2 meters, causing discomfort to drivers and concern for officials. The Palau government commissioned two studies by Louis Berger International and Japan International Co-operation Agency. They both concluded that the bridge was structurally safe though 1m more of creep would occur in the future. Based on the studies, the Palau government decided to counteract the cosmetic damage caused by creep with resurfacing and reinforcement of the bridge.

  1. The bridge midspan was modified, changing the originally non-weight-bearing hinged joint to a continuous block of concrete.
  2. Eight prestress cables were added to straighten the span.
  3. Eight flat-jacks were added to the center of the structure to add additional prestress, loading the center of the bridge.
  4. The bridge was resurfaced to smooth out the sagging road.

The most probable progression of the collapse began with a weakening of the Babeldaob side. This caused a shear failure, resulting in all of the weight of the continuous main span coming to rest on the Koror side. This unbalanced moment caused the backspan of the Koror side to fail and tipped the bridge into the channel. The new design of the bridge hastened the bridge's collapse, but did not actually cause the fatal weakening of the Babeldoab flange. The ultimate cause of collapse remains unknown. The repair and resurfacing operation may have contributed to the bridge failure, but since the lawsuit over the collapse was settled out of court, no final cause has ever been definitively published.

下面的分析只是外界的议论,由于各方庭外和解,最终调查结果未公布,成为塌桥疑案。

帕劳(Palao)Koror 桥的倒塌 - liu-xiaoyao - 我的博客
体外预应力&跨中推顶
帕劳(Palao)Koror 桥的倒塌 - liu-xiaoyao - 我的博客
计算应力
帕劳(Palao)Koror 桥的倒塌 - liu-xiaoyao - 我的博客

倒塌(1997年3月)
帕劳(Palao)Koror 桥的倒塌 - liu-xiaoyao - 我的博客
 临时索桥(1998年)& 重建矮塔斜拉桥(2002年10月)
帕劳(Palao)Koror 桥的倒塌 - liu-xiaoyao - 我的博客

It was built by the Kajima Corporation of Japan in 2002.

帕劳(Palao)Koror 桥的倒塌 - liu-xiaoyao - 我的博客
 
 参考资料
 [1]Chris Burgoyne MA, MSc, PhD, CEng, FIStructE,MICE University of Cambridge Richard Scantlebury BA, MEng Benaim (UK) Ltd.Why did Palau Bridge collapse?
 [2]http://fr.wikipedia.org/wiki/Pont_de_Koror-Babeldaob
[3]http://en.wikipedia.org/wiki/Koror%E2%80%93Babeldaob_Bridge
  评论这张
 
阅读(853)| 评论(2)
推荐 转载

历史上的今天

在LOFTER的更多文章

评论

<#--最新日志,群博日志--> <#--推荐日志--> <#--引用记录--> <#--博主推荐--> <#--随机阅读--> <#--首页推荐--> <#--历史上的今天--> <#--被推荐日志--> <#--上一篇,下一篇--> <#-- 热度 --> <#-- 网易新闻广告 --> <#--右边模块结构--> <#--评论模块结构--> <#--引用模块结构--> <#--博主发起的投票-->
 
 
 
 
 
 
 
 
 
 
 
 
 
 

页脚

网易公司版权所有 ©1997-2017