Method for monitoring Lamb wave engineering structural damage by utilizing signal decomposition

Abstract

The invention discloses a method for monitoring Lamb wave engineering structural damage by utilizing signal decomposition, which comprises the following steps: collecting the Lamb wave healthy reference signals fhji of an engineering structure in a healthy state, wherein i and j can be 1, 2, 3,...; when the structure is damaged, collecting all the Lamb wave response signals f'ji of the damaged structure under the condition of an inspiring / sensing channel; utilizing the correlation operation to extract all the Lamb wave damage scattered signals of the damaged structure under the condition of the inspiring / sensing channel; obtaining the damage position and scope according to the characteristic parameters acquired in the steps above, thereby analyzing and judging the health condition of the monitored structure. According to the method, based on the condition of the traditional structural damage monitoring device, the Lamb wave damage scattered signals in a damage monitoring system are extracted by using the related treatment, thereby increasing the accuracy and stability of the monitoring system.

Description

technical field

[0001] The invention relates to a method for active Lamb wave damage monitoring of plate engineering structures, in particular to a method for extracting Lamb wave structure damage scattering signals in active health monitoring so as to correctly realize engineering structure damage monitoring. Background technique

[0002] With the continuous improvement of structural safety and reliability requirements, the on-line monitoring and diagnosis of structural damage has attracted more and more attention. In order to prevent disasters or losses caused by structural damage, effective monitoring of plate structures is necessary.

[0003] The on-line monitoring of structural damage requires that the relevant signal generation and acquisition equipment should be relatively simple, and the monitoring must have high accuracy and real-time performance. The damage monitoring of plate structures generally adopts the method of active Lamb wave, that is, a certain number of ...

Examples

Embodiment Construction

[0035] The implementation process of the present invention will be described in detail below in conjunction with the accompanying drawings.

[0036] The invention provides a Lamb wave engineering structure damage monitoring method utilizing signal decomposition, comprising the following steps:

[0037] (1) Arrange a group of piezoelectric elements on the engineering structure to be monitored to form a sensing / excitation array, where the piezoelectric element used as the excitation element is set to P j , and the piezoelectric element as the sensing element is set to P i ,and i,j =1,2,3,...;

[0038] In this example, with figure 1 As shown, take i =1, 2, j =1, the three piezoelectric elements are all fixed on the test piece, the said test piece is an epoxy glass fiber reinforced composite material plate, the size is 800mm×200mm×2mm; the three piezoelectric elements are arranged in a straight line, to test The center point of the part is the coordinate origin, and the c...

technical field

[0001] The invention relates to a method for active Lamb wave damage monitoring of plate engineering structures, in particular to a method for extracting Lamb wave structure damage scattering signals in active health monitoring so as to correctly realize engineering structure damage monitoring. Background technique

[0002] With the continuous improvement of structural safety and reliability requirements, the on-line monitoring and diagnosis of structural damage has attracted more and more attention. In order to prevent disasters or losses caused by structural damage, effective monitoring of plate structures is necessary.

[0003] The on-line monitoring of structural damage requires that the relevant signal generation and acquisition equipment should be relatively simple, and the monitoring must have high accuracy and real-time performance. The damage monitoring of plate structures generally adopts the method of active Lamb wave, that is, a certain number of ...

Examples

Embodiment Construction

[0035] The implementation process of the present invention will be described in detail below in conjunction with the accompanying drawings.

[0036] The invention provides a Lamb wave engineering structure damage monitoring method utilizing signal decomposition, comprising the following steps:

[0037] (1) Arrange a group of piezoelectric elements on the engineering structure to be monitored to form a sensing / excitation array, where the piezoelectric element used as the excitation element is set to P j , and the piezoelectric element as the sensing element is set to P i ,and i,j =1,2,3,...;

[0038] In this example, with figure 1 As shown, take i =1, 2, j =1, the three piezoelectric elements are all fixed on the test piece, the said test piece is an epoxy glass fiber reinforced composite material plate, the size is 800mm×200mm×2mm; the three piezoelectric elements are arranged in a straight line, to test The center point of the part is the coordinate origin, and the c...

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