Thermoelastic stress analysis and structural health monitoring: An emerging nexus

Recent innovations in thermal-detector technology are shown to foster the development of an in situ structural health monitoring capability based on thermoelastic stress analysis, a powerful full-field stress-measurement technique that offers an attractive set of diagnostic and prognostic capabilities, some of which are not found in any of the established structural health monitoring modalities. After reviewing these capabilities, the article examines an experimental case study involving the monitoring of an F/A-18 airframe structure subject to full-scale fatigue testing under representative flight spectrum loading spanning nearly one aircraft life time. The case study confirms the viability of the concept and also highlights some of its primary limitations.

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