Beam structure damage identification method based on multi-scale strange attractor prediction errors

Abstract

The invention discloses a beam structure damage identification method based on a multi-scale strange attractor prediction error. The method specifically comprises the following steps: acceleration response data of a beam structure is acquired by a sensor system; the acceleration data is denoised by adopting a soft threshold method; smooth discrete wavelet decomposition is conducted on denoised signals to obtain non-down-sampled multi-scale signals; phase space reconstruction is conducted on the multi-scale signals by applying a phase space reconstruction theory, multi-scale reconstructed attractors MRA are obtained and subjected to normalization processing to obtain MRAN; and the multi-scale strange attractor prediction error PE is calculated, and according to the multi-scale strange attractor prediction error PE, the health state of a beam structure is judged, and the damage degree of the beam structure is identified. According to the built multi-scale strange attractor prediction error method, limitation of the simulation form is broken through, the characteristics that the damage sensitivity and the identification accuracy are high are achieved, and the damage degree of the beamstructure can be accurately identified only by adopting the single point acceleration data.

Description

technical field [0001] The invention relates to a beam structure damage identification method, in particular to a beam structure damage identification method based on multi-scale singular attractor prediction errors, and belongs to the field of structural damage diagnosis. Background technique [0002] In the long-term service of the beam structure, due to the degradation of its own materials and the influence of the complex environment, damage will inevitably occur. The evolution and accumulation of early local damage will threaten the reliable operation and safety of the overall structure, and even lead to overall failure. Based on this, the rapid progress of structural nondestructive testing technology has been made in the past two decades, and it has played an irreplaceable role in timely detection of early structural damage. The strange attractor prediction error method is a new structural nondestructive testing method with the rapid development of chaos theory, and is ...

AI Technical Summary

Problems solved by technology

However, the use of wavelet transform to improve the traditional strange attractor to obtain a new multi-scale strange attractor prediction error, and the research on beam structure damage identification based on it has not been reported yet

[0003] The traditional beam structure damage detection method based on the singular attractor prediction error has strict requirements on the excitation form, and generally needs to select a chaotic excitation with a specific Lyapunov exponent according to the structural characteristics; while conventional excitation, such as hammer excitation, simple harmonic excitation, etc. , which cannot meet the above incentive selection requirements, will reduce the accuracy and stability of the singular attractor prediction error method in damage identification

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