PSI - Issue 52

Alessandro De Luca et al. / Procedia Structural Integrity 52 (2024) 424–429 Alessandro De Luca / Structural Integrity Procedia 00 (2019) 000 – 000

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Figure 4. Simulated damage position.

3. Results Figure 5 shows an example of the reference signal recorded in the unloaded/undamaged configurations at a frequency of 200 kHz.

Figure 5. S 0 and A 0 mode

Figure 6 (left column) show how the amplitudes of the signal envelopes are affected by the load. In particular, it can be observed that for sensor paths located along the load direction (act 4- rec 2) the amplitudes of the signals increase as the load increases; conversely, the amplitudes of the signals decrease for sensor paths transversely placed (act 4 – rec 5). No significant changes are evident along the oblique direction (act 4 – rec 3). The signal recorded in the undamaged and damaged configurations under the different load levels were compared, Figure 6 (right column). According to Figure 6 (right column) the presence of both damage and loads affects the signal amplitudes. In detail, it can be noticed that damage (positioned along the path 4-2) reduces the amplitude of the signal, while the presence of the load increases it. It is therefore evident that under certain damage and loading conditions, the two phenomena may compensate each other, resulting in false positives or, conversely, false negatives.