Vibration measurement of railway bridge with seismic low-frequency transducer based on signal reconstruction technique

摘要

Abstract: Aiming at the characteristic of bridge dynamic deflection signal, and the requirement for the frequency characteristics of measuring transducer, after reviewing several measuring methods, the authors put forward a convenient and effective method for measurement of bridge dynamic deflection with seismic low frequency vibration transducers. Signal recovery technique is adopted to compensate the output which is distorted because of the frequency characteristics of seismic transducer. Spectrum extrapolation technique for time-limited signal is employed to reconstruct some low frequency spectral lines which are contaminated seriously by low frequency noise. The work in this paper provides a new way for the measurement of bridge dynamic deflection, which lays the foundation for the measurement and research of bridge spatial vibration excited by a train passing by. !6