基于小波变换的斜拉桥索双轴漏磁检测方法

针对在役斜拉桥索只能进行无损检测的特点,提出了基于漏磁检测的缆索缺陷探伤方法以及检测电路.由于检测现场空间磁场噪声较强,导致漏磁信号特征不明显,为此,应用二进小波变换的方法,对周向漏磁信号采用基于高斯白噪声的快速离散软阈值算法进行信噪分离,以确定缆索缺陷程度;对轴向漏磁检测信号进行奇异性检测处理,以获取缺陷的精确位置信息.实验结果表明,该方法可实时获取缆绳索缺陷程度和位置信息.

Extraction Method on Wavelet Signals of Double Axis Magnetic Leakage Field for a Cable Stayed Bridge

An inspection method and circuit by magnetic leakage field are offered for cables,due for which the test of an active cable stayed bridge must be only lossless.In order to reduce noise of space magnetic field during the work environment that of result in an unclear signal character,a discrete soft threshold algorithm on the Gaussian white noise is applied to separate signal and noise for circumference magnetic field of a checked cable by the dyadic wavelet transform for the sake of the fault size.In order to obtain the precise fault location,a singularity analysis is applied for oriental magnetic field of the cable by the singular point of signal waveform.The experiment results showed that it will be obtained the real-time information of fault degree and location to the checked cable by the new approach,so that the credible proof will be given about detection and analysis to the broken wires for the cable stayed bridge.