Online real-time monitoring method and system for structural damage

Abstract

The invention discloses an online real-time monitoring method and system for structural damage. According to the method or the system, a set empirical mode decomposition algorithm is utilized on microvibration response signals in the direction perpendicular to a structure to obtain a first stage natural frequency and a second stage natural frequency, and whether the first stage natural frequency and the second stage natural frequency are equal to a natural frequency of an undamaged structure is judged; if so, that the surface of the structure is not damaged is determined; if not, that the surface of the structure is damaged is determined, and energy values of different measurement points of different slide times are calculated out; whether the energy value of some measurement point of different slide times is equal to that of a corresponding measurement point of the undamaged structure is compared; if so, that the measurement point is not damaged is determined; if not, that the measurement point is a damaged position is determined. Therefore, the method or the system disclosed by the invention can be used for detecting transient micro damage of the structure and determining the damaged position in real time under the high-frequency and high-speed background conditions.

Description

technical field [0001] The invention relates to the field of structural damage diagnosis, in particular to an online real-time monitoring method and system for structural damage. Background technique [0002] On-line structural damage detection and diagnosis is an important aspect of structural damage diagnosis. Most of the methods proposed in this regard are based on the change of model parameters (natural frequency, mode shape, mode shape curvature, etc.) or the use of finite element model modification technology. The essence of damage diagnosis and identification based on vibration signals is a process of extraction and analysis of dynamic signal statistical characteristics. At present, there are many theoretical studies on vibration modal parameter identification and damage detection. Early studies include: Yuen proposed a method to determine the damage location according to the slope change rate of the mode shape to locate the damage of the structure; Aktan et al. stud...

AI Technical Summary

Problems solved by technology

Under the conditions of large current carrying, high speed and high frequency, the surface of high-speed sliding electric contact slide rail is prone to micro damage, such as: ablation, abrasion, planing and other damage phenomena, which seriously affect the work efficiency, and high-speed sliding electric contact slide rail Inside the mechanical system, it is in an invisible area, and the above methods cannot be used for damage detection

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