台风“麦莎”作用下润扬悬索桥抖振响应实测研究

Field measurement on buffeting response of Runyang Suspension Bridge under typhoon Matsa

既有桥梁抖振响应的现场实测研究,是桥梁风工程研究领域的重要手段之一。2005年8月,台风"麦莎"突袭江苏,本文以遭受该台风袭击的润扬长江大桥南汊悬索桥为工程背景,利用该桥结构健康监测系统(SHMS)中风速仪和加速度传感器实时采集的数据,采用时频分析和统计方法对大跨悬索桥的抖振响应进行了现场实测案例研究,主要研究内容包括桥址区的强风特性分析、主梁和缆索振动响应特性分析、振动与风速的关系等。研究结果可用于验证现有抖振理论分析方法的可靠性,同时为其它同类型大跨缆索承重桥梁的抗风设计提供参考。

Field measurement on buffeting response of existing bridges is an important research approach of Bridge Wind Engineering. Runyang Suspension Bridge （RSB）, the longest suspension bridge in China is taken as a ease study. In order to provide field measurement data for wind-resistant safety evaluation, 2 anemometers and 85 accelerometers were installed in structural healthy monitoring system （SHMS） of RSB. When typhoon Matsa passed through Jiangsu in August 2005, the SHMS wholly recorded the typhoon and structural vibration responses. Based on the time-frequency technique and statistical theory, the measurement data are analyzed to obtain the wind characteristics, the response characteristics of cable and deck, the variation of acceleration response RMS vs. wind velocity, etc. Results obtained in this paper can be employed to validate the reliability of current buffeting response calculation techniques, and provide reference values for wind-resistant design of other long-span cable-stayed bridges.