In this paper, electromechanical impedance method was utilized in order to detect moisture level changes in carbon fiber reinforced polymer composites. Due to electromechanical coupling of piezoelectric transducers, glue layer and host structure mechanical resonances are visible in the electric impedance spectrum of transducer. Appearance of additional resonance peaks, their shift in frequency or magnitude change can be treated as indicator of damage or anther anomaly present in the host structure. Research presented in this paper shows that moisture content also has influence on electromechanical resonant peaks.
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