Global-local damage localization and imaging in beam structures using laser-measured natural frequencies and guided wavefields

• Published in: Measurement : journal of the International Measurement Confederation Vol. 236; p. 115061
• Main Authors: Sha, Ganggang, Xiao, Wen, Zuo, Hongfu, Cao, Maosen, Radzieński, Maciej, Ostachowicz, Wiesław
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.08.2024
• Subjects: Damage imaging; Global-local approach; Guided wavefield; Laser vibration measurement; Natural frequency; Natural frequency; Global-local approach; Guided wavefield; Laser vibration measurement; Damage imaging
• ISSN: 0263-2241
• DOI: 10.1016/j.measurement.2024.115061

•A global–local approach for damage localization and imaging in beam structures is formulated.•Damage-induced relative natural frequency change curves are derived analytically and then used for global damage localization.•A TKEO-wavelet-wavefield analysis method is created for local damage imaging in the spatial domain.•The global–local approach offers high accuracy and efficiency in damage imaging by reducing wavefield measurements by 80%. The guided wavefield-based damage imaging methods have been the subject of extensive research. It is commonly recognized that these methods are time-consuming due to measurements of high-resolution guided wavefields. To address this challenge, this paper introduces a global–local damage localization and imaging approach in beam structures. Firstly, a global damage indicator is developed to identify possible damage locations through the analysis of relative natural frequency change curves. Subsequently, inspections of these possible damage locations are conducted using guided wavefields. To process the laser-measured wavefields, wavelets are employed in conjunction with a Teager-Kaiser energy operator (TKEO), resulting in the generation of TKEO-wavelet-wavefields. The multi-scale property of the TKEO-wavelet-wavefields helps minimize measurement noise and enhance the detection of damage-related wavefield anomalies, thereby improving the accuracy of the inspection process. Experimental results demonstrate that the global–local approach exhibits high accuracy and efficiency in damage imaging, while reducing wavefield measurements by 80%.