APPLICATION OF PIEZOELECTRIC MFC SENSORS AND FIBRE BRAGG GRATING SENSORS IN STRUCTURAL HEALTH MONITORING OF COMPOSITE MATERIALS

摘要

Advanced composite materials have been integrated extensively into aircraft structures and have been emerged in civil infrastructure (e.g. bridges), in recent years. Composite materials are prone to initiation of hidden damage which makes it vital to detect damage at its onset. In this paper, first we introduce a procedure to fabricate structural carbon fiber reinforced polymer (CFRP) sheets at the university laboratory. Then, two structural health monitoring (SHM) systems will be developed to assess and monitor the performance of CFRP materials. The first SHM system is based on installing piezoelectric MFC sensors on CFRP sheets. These sensors are using guided lamb waves to detect possible damage in composites at its onset. The second SHM system will be developed using Fiber Bragg Grating (FBG) technology. This system will acquire signals from a fiber optic thermocouple and a fiber optic strain gauge. The damage will be introduced into CFRP sheets with an impact hammer. The damage detection will be performed by the two SHM systems for different damage severities. The pros and cons of each SHM system in composite damage detection will be investigated and the recommendations will be made for utilizing each system in real world composite applications.