Analysis of detection signal and realization on evaluation system of bolt anchoring quality based on sound wave testing

According to the experimental research on acoustic properties of bolt anchorage system in loading conditions and the theory on sound wave testing,it shows that anchorage system quality can be estimated by concretion wave velocity and bolt workload state.Reflection signal of bolt bottom,which is key to determine concretion wave velocity,could be identified exactly by analyzing the highest frequency reconstruction signal of decomposed original signal with db4 wavelet in 4 or 5 scale.On the reconstruction signal curve,the starting point of the second crest is just bottom reflection time point.Integral reflection signal of bolt bottom was obtained by using Self-adaptive Filtering method that let reference signal approach detection signal.The two means have a good coherence.Bolt workload is 3-power function of detection signal's base band got by spectrum analysis.Nondestructive detection signal analysis system of anchorage quality is written based on Matlab and applied in practice to improve analysis precision and achieve intelligence assessment.