韩国圣水大桥连续垮塌过程分析  

Progressive Collapse Analysis of Seongsu Bridge in South Korea

作　　者：叶华文[1] 黄若森 刘吉林 王天琦 黄小军 YE Hua-wen;HUANG Ruo-sen;LIU Ji-lin;WANG Tian-qi;HUANG Xiao-jun(School of Civil Engineering, Southwest Jiaotong University, Chengdu 610031, China;China Railway Erju 4th Engineering Co. , Ltd. , Chengdu 610300, China)

机构地区：[1]西南交通大学土木工程学院,四川成都610031 [2]中铁二局第四工程有限公司,四川成都610300

出　　处：《世界桥梁》2021年第5期87-93,共7页World Bridges

摘　　要：韩国圣水大桥为(249+84+5×120+84+143)m钢桁悬臂梁桥,在服役15年后发生垮塌。综合既有研究资料,采用有限元模拟和疲劳试验等方法,从结构设计、制造施工和运营维护等方面对其垮塌原因和失效过程进行分析。结果表明:事故始于10号墩南侧悬臂梁1根竖杆疲劳断裂,荷载重分布导致该截面其余竖杆破坏,销栓被剪断,悬跨梁失去北侧支撑落入江中;设计时未充分考虑交通量的远期发展和结构冗余度不足是垮塌的主要原因;悬臂段与悬跨梁间铰接竖杆的焊缝未按设计要求进行全熔透焊接施工,且焊缝附近区域母材厚度过渡段坡度远大于设计值,有限元分析得到焊缝处应力集中系数较设计值增大1倍,明显降低了疲劳强度,是导致垮塌的直接原因;运营期桥梁缺乏维护和监测,轻视结构局部腐蚀和损伤问题,也是导致垮塌的重要原因。The Seongsu Bridge is a steel truss cantilever bridge with span arrangement of 249,84,5×120,84 and 143 m,which collapsed after serving for 15 years.Based on the existing research,finite element simulation and fatigue test,the causes and failure process are investigated from aspects of the structural design,manufacturing,construction and maintenance.The accident started when a vertical member of the cantilever beam on the south side of pier 10 was fractured.The load redistribution caused damage to the remaining vertical members,then the pin was sheared to break,and the suspension beam lost the support on the north side and fell into the river.The analysis results show that the underestimation of long-term transportation growth and the insufficient structural redundancy are the main causes of the collapse;the stress concentration factor is significantly increased due to the off-design partial penetration weld and abrupt adjacent transition section of the hinged vertical member connecting the cantilever section and the suspended span,and the consequent low fatigue strength directly leads to the fracture of the vertical member and the bridge collapse.Moreover,the lack of systematic maintenance and effective monitoring and overlooking local corrosion and damage during the operation period are also causes of the collapse.

关 键 词：圣水大桥 钢桁悬臂梁桥 垮塌 结构冗余度 疲劳破坏 

分 类 号：U448.214[建筑科学—桥梁与隧道工程] U445.7[交通运输工程—道路与铁道工程]