Damage identification method for beam structures based on multi-scale singular attractor prediction errors

Abstract

The invention discloses a beam structure damage identification method based on multi-scale singular attractor prediction errors. The method specifically includes the following steps: collecting acceleration response data of the beam structure through a sensor system; denoising the acceleration data by using a soft threshold method; Perform stationary discrete wavelet decomposition on the denoising signal to obtain multi-scale sub-signals without downsampling; apply phase space reconstruction theory to reconstruct the phase space of multi-scale sub-signals, obtain multi-scale reconstruction attractor MRA, and perform After normalization processing, the MRAN is obtained; the multi-scale singular attractor prediction error PE is calculated, and the health status of the beam structure is judged according to it, and its damage degree is identified. The multi-scale singular attractor prediction error method established by the invention breaks through the limitation of the excitation form, and has the characteristics of strong damage sensitivity and high identification accuracy, and can accurately identify the damage degree of the beam structure only by using 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 structure 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 damage. Based on this, in the past two decades, the technology of non-destructive testing of structures has made rapid progress, which has played an irreplaceable role in the timely detection of early structural damage. Singular attractor prediction error method is a new non-destructive testing method for structures with the rapid development of chaos theory, and ...

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

Images