Automatic Identification of Fundamental Frequency for Tied Arch Bridge Suspender Tension Monitoring

Abstract

For the reliable assessment of bridge health and safety conditions, it is crucial to identify fundamental frequencies of suspender real time and automatically from random vibration signal that is weak and interfered with noise when suspender tension is measured online by frequency method. According to the characteristics of vibration signal spectrum, auto-power spectrum combined with autocorrelation function method which result was periodic distribution of spectral information in frequency domain. Plus from the spectrum the resonant peak of suspender was highlighted to reduce the noise disturbance which helped identify fundamental frequency and improved identification effect and result precision. In addition a field experiment in a tied arch bridge was carried out to analyze the collected vibration data. The practical application shows that this kind of measurement method is feasible and useful.