摘要
为了解决桥梁结构振动监测中模态频率监测不完整和不准确的问题,采用全球导航卫星系统(GNSS)接收机和加速度计在英国诺丁汉威尔福德悬索桥进行监测试验,使用监测点装置、精密时间采集器解决监测点多传感器同轴、时间同步问题,同步采集GNSS实时动态差分(RTK)、网络RTK、后处理模式数据和加速度计数据,设计切比雪夫-自适应滤波方法识别桥梁结构动态位移。分析结果表明:GNSS易识别低值模态频率,加速度计易识别高值模态频率,2种传感器均可识别出重叠频带的模态频率,且结果吻合;2种传感器识别的动态位移吻合,两者差值的标准差和平均偏差均小于1mm;联合监测方法既适用于低频率、大振幅振动的大跨径桥梁监测,也适于高频率、小振幅振动的中小跨径桥梁监测。
To guarantee the integrality and accuracy of monitoring structural the experiment was conducted on the Nottingham Wilford Suspension Bridge and accelerometer. A special cage and a precise time data logger were made vibration of bridges, using GNSS receiver by the University of Nottingham to guarantee the same monitoring site and time synchronization. Accelerometer and GNSS data with three modes of conventional RTK, network RTK and post-processing were collected synchronously. The vibration displacements were identified by the designed filtering method integrating adaptive filter and Chebyshev filter. The results show that the GNSS receiver and accelerometer can detect low and high frequencies respectively. The frequencies identified by both sensors are similar in overlapping frequency band. The dynamic displacements identified by both sensors are similar with the standard deviation and mean value being less than 1 mm. The integrating method for bridge dynamic monitoring can be used for long-span bridges with low frequency and large amplitude vibration, and for the small or medium-span bridges with highfrequency and small amplitude vibration.
出处
《中国公路学报》
EI
CAS
CSCD
北大核心
2014年第2期62-69,共8页
China Journal of Highway and Transport
基金
国家自然科学基金项目(50908083)
关键词
桥梁工程
结构健康监测
全球导航卫星系统
模态频率
加速度计
bridge engineering
structure health monitoring
global navigation satellite system
modal frequency
accelerometer
