基于时限信号重构技术的桥梁动挠度惯性测量方法

Inertial measurement method for bridge dynamic deflection based on time-limited signal reconvery technique

以惯性测量原理，用地震式低频振动传感器测量桥梁动挠度。利用信号恢复技术，对地震式低频振动传感器因频率特性而畸变的输出作补偿处理。讨论系统存在零点时的恢复技术，及噪声下信号恢复处理的不适定性问题。以铁路桥梁动挠度的部分时域特征，采用时限信号低频频谱重构技术，外推信噪比差的部分低频谱线，有效地反演原始信号。本文为列车激励下桥梁空间振动形态提供了十分便捷有效的测量方法。

An inertial measurement method for bridge dynamic deflection with seismic low frequency vibration transducers was promoted. Signal recovery technique is adopted to compensate the output which is distorted because of the frequency characteristics of seismic transducer. In connection with partial characteristics of the waveform of bridge dynamic deflection signal derived from the theoretic model of interaction between train and bridge, 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 provides a new way for convenient and effective measurement and research of bridge spatial vibration excited by a train passing by.