Logowanie do System sprawozdań KDM

Comparative study of thermal degradation of GFRP composites using fiber bragg grating, electromechanical impedance and guided waves based methods

Kierownik projektu: Wiesław Ostachowicz

Instytut Maszyn Przepływowych PAN w Gdańsku

Gdańsk

Streszczenie projektu

The aim of the experiment is to perform comparative study of three distinct damage detection techniques (Strain, Guided waves (GW) and electromechanical impedance (EMI)) for thermally induced damage on GFRP sample due to localized heating with an air gun on a glass-fiber reinforced polymer composite samples. The FBG sensors are sensitive to strain, and temperature. They may be used for tracking the neutral axis (NA) of the structure, which has been shown to be a damage sensitive feature. NA is insensitive to ambient loading and presence of measurement noise. The other two methods (GW and EMI) make use of piezoelectric principle for actuating and sensing. For the GW technique, the piezo sensor (PZT) excites a guided wave which can propagate long distances with minimum attenuation in the structure and is reflected from structural discontinuities. By processing the wave reflections at different sensor locations deterioration in the sample can be detected. The EMI method makes use of the electro-mechanical coupling and the condition of the structure is investigated in terms of the electrical parameters' admittance and impedance. By detecting the change in these quantities, the damage in the structure can be detected. The root mean square deviation (RMSD) between the healthy and the damaged condition is used as the metric for damage detection. Finally numerical simulation of the experimental samples are performed on ABAQUS to analyze their behavior to thermal damage and to validate the experiment.