Real-time identification and monitoring early warning method for vortex vibration event of large-span suspension bridge

Abstract

The invention discloses a real-time identification and monitoring early warning method for a vortex vibration event of a large-span suspension bridge. The method comprises the following steps: firstly, calculating a frequency spectrum of a bridge monitoring acceleration signal; determining a high-pass filtering cut-off frequency according to the bridge first-order frequency corresponding to the frequency spectrum first-order energy peak value, removing low-frequency noise interference in the signal through filtering, and calculating real-time vibration displacement of the bridge by adopting a recursive acceleration integration method; and carrying out real-time recursive Hilbert transform on the integral displacement data to obtain a real part and an imaginary part of signal data, and carrying out complex plane expression and evaluation on signals to realize vortex vibration identification and early warning. The method has the advantages of high real-time performance, high precision, accuracy and intuition; and the vibration characteristics of the bridge during vortex vibration are identified and measured online in real time, and vortex vibration early warning and online monitoring of the bridge are carried out.

Description

technical field [0001] The invention relates to the field of long-span bridge structure monitoring, in particular to a method for real-time identification, monitoring and early warning of vortex vibration events of long-span suspension bridges. Background technique [0002] Bridge vortex induced resonance is an important vibration problem in bridge operation, and it is a phenomenon of limiting vibration of the main girder caused by vortices that periodically shed alternately. Although bridge vortex vibrations are not like flutter, galloping and other divergent vibrations that can cause bridge dynamic instability and damage, vortex vibrations are easy to occur at low wind speeds, and large amplitudes can cause fatigue of bridge cables and other structures. It will affect driving comfort and driving safety. Therefore, real-time online identification and early warning of bridge vortex vibration is very important, and it is the basis for bridge operation and maintenance manageme...

AI Technical Summary

Problems solved by technology

Based on the vortex vibration characteristics of bridges, the current bridge vortex vibration identification is mainly to identify the stable sinusoidal vibration segment in the bridge monitoring data with the naked eye, or to perform spectrum analysis on a segment of data and manually judge whether there is only a single spectrum peak. The disadvantage of the method is that the human naked eye judgment error is large, inaccurate, and it is easy to misjudge or miss judgment; the batch spectrum analysis method cannot judge online in real time

Moreover, neither of the above two methods can accurately perceive the occurrence and end time of vortex vibration

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