In the present paper a method for the Structural Health Monitoring (SHM) of bonded lap joints is presented. This method is based on the interference of elastic waves generated by piezo sensors and travelling along thin bonded plates through the adhesion area. Tone bursts of different extension were generated and, when they encountered the debonded area, the wave speed changed. This affected the wave reflection at the boundary of the disbond and the subsequent interference of the reflected wave with the main wave travelling along the joint. Destructive interference conditions were promoted when the adhesive was partially debonded and this was related to the length of the disbond. In the present study numerical simulations based on finite elements were performed and compared with a simplified analytical model describing the Lamb waves propagation through the joint. The simulation results were subsequently compared with the experimental data and a good agreement was found: the proposed method was simple, straightforward and its application on thin single lap joints provided reliable results.
Elastic waves interference for the analysis of disbonds in single lap joints
Nicassio F.;Carrino S.;Scarselli G.
2019-01-01
Abstract
In the present paper a method for the Structural Health Monitoring (SHM) of bonded lap joints is presented. This method is based on the interference of elastic waves generated by piezo sensors and travelling along thin bonded plates through the adhesion area. Tone bursts of different extension were generated and, when they encountered the debonded area, the wave speed changed. This affected the wave reflection at the boundary of the disbond and the subsequent interference of the reflected wave with the main wave travelling along the joint. Destructive interference conditions were promoted when the adhesive was partially debonded and this was related to the length of the disbond. In the present study numerical simulations based on finite elements were performed and compared with a simplified analytical model describing the Lamb waves propagation through the joint. The simulation results were subsequently compared with the experimental data and a good agreement was found: the proposed method was simple, straightforward and its application on thin single lap joints provided reliable results.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
