环境风场长期作用下某大跨悬索桥抖振疲劳寿命分析  

The fatigue life analysis of a long-span suspension bridge under long-term environmental wind action

作　　者：胡俊[1,2] 欧进萍[3] 

机构地区：[1]重庆交通大学山区桥梁与隧道工程国家重点实验室培育基地,重庆400074 [2]重庆交通大学土木建筑学院,重庆400074 [3]大连理工大学土木工程学院,辽宁大连116024

出　　处：《振动工程学报》2014年第1期60-66,共7页Journal of Vibration Engineering

基　　金：国家自然科学基金重点资助项目(90815022);山区桥梁与隧道工程国家重点实验室培育基地(重庆交通大学)开放基金资助项目(CQSLBF-Y13-7)

摘　　要：为探讨环境风场长期作用下大跨悬索桥的抖振疲劳,基于东海某大跨度悬索桥的风场监测系统,对桥址处的平均风速进行了现场的连续观测,针对两年的实测结果,探讨了桥位处"疲劳风"的风速风向分布规律;同时基于风速分解,提出考虑风向影响的结构抖振疲劳时域分析方法,并以东海悬索桥为对象进行了探讨。结果表明,疲劳风速分布表现为正偏态,同时能很好地采用Weibull分布进行拟合;该桥加劲梁的风振疲劳损伤对风速的变化非常敏感,在运营过程中,强风作用下加劲梁损伤应受到重视;根据桥位处的疲劳风速风向分布,得到各风向风速的发生概率及持续时间,该桥加劲梁的风振疲劳寿命远大于桥梁结构的设计使用期100年。To analyze the buffeting fatigue of the long-span suspension bridge under the environmental wind action,the wind field monitoring system was installed on a long-span suspension bridge in the East China Sea and the long-term wind speeds were collected.Based on two years experimental results,the distributions of wind speed at different wind directions were discussed; also the time-domain fatigue analysis method considering the wind direction effect was proposed based on the wind speed decomposition.The suspension bridge in the East China Sea is analyzed in detail and the results indicate that the fatigue wind speed can be well fitted by Weibull distribution.The stiffening girder＇s fatigue is very sensitive to the wind speed and the role of strong winds should be taken seriously,the bridge＇s buffeting fatigue life is much longer than the bridge＇s structural design life of 100 years according to the probability of occurrence and duration of the wind speed in different directions.

关 键 词：悬索桥 抖振 疲劳 现场实测 疲劳风 

分 类 号：U448.25[建筑科学—桥梁与隧道工程] U441.4[交通运输工程—道路与铁道工程]