Damage detecting method of platy structure

Abstract

The invention relates to a damage detecting method of a platy structure. The damage detecting method comprises the following steps of (S1) arranging a piezoelectric transducer array on the platy structure; (S2) establishing a benchmark database; (S3) collecting a current signal and a current temperature of the platy structure to be detected; (S4) calculating a difference signal which is equal to acurrent baseline signal in the benchmark database subtracts the current signal; (S5) calculating a damage index according to the difference signal and the current baseline signal, if the damage indexis greater than a preset threshold, judging that the platy structure to be detected is damaged, and if the damage index is no more than the preset threshold, judging that the platy structure to be detected is not damaged. The damage detecting method has the beneficial effects that due to adoption of a temperature compensation mode, the influence caused by larger temperature change is weakened inthe process of using piezoelectric transducers to detect the damage of the platy structure, so that the detection accuracy is improved and the potential safety hazards are avoided.

Description

technical field [0001] The invention relates to the technical field of structure detection, in particular to a damage detection method for a rail vehicle plate structure. Background technique [0002] At present, piezoelectric intelligent detection technology, as a kind of structural health detection technology, can carry out regional detection, is easy to integrate with structures, and is widely used in damage detection of composite materials and metal structures. In the existing technology, in the method of detecting structural damage through piezoelectric transducers, since the detection environment is mostly indoors and the environmental conditions are relatively stable, the influence of temperature on the detection results is not considered, but the change of temperature will make the structure The phenomenon of thermal expansion and contraction occurs, which affects the wave propagation in the structure to be detected, and then affects the accuracy of structural damage...

AI Technical Summary

Problems solved by technology

In the existing technology, in the method of detecting structural damage through piezoelectric transducers, since the detection environment is mostly indoors and the environmental conditions are relatively stable, the influence of temperature on the detection results is not considered, but the change of temperature will make the structure The phenomenon of thermal expansion and contraction occurs, which affects the propagation of waves in the structure to be detected, which in turn affects the accuracy of structural damage detection

[0003] When performing damage detection on key parts such as the EMU car body, due to the change of the external environment temperature or the temperature difference between the transformer in the working state and the transformer in the stopped state when the train is running, the key parts located around it The temperature of the structure also rises accordingly. At this time, if the damage detection of these key structures is carried out, the piezoelectric transducer is used for detection but the temperature factor is not considered, the detection accuracy will be affected, and there will be a large safety hazard.

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