Issue 70

S.K. Shandiz et alii, Frattura ed Integrità Strutturale, 70 (2024) 24-54; DOI: 10.3221/IGF-ESIS.70.02

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Figure 19: Normalized instantaneous energy of IMF extracted through VMD for cases (a) P1, (b) P2, (c) P3, (d) A1, (e) A2, (f) A3, (g) B1, (h) B2, (i) B3, (j) C1, (k) C2, (l) C3 with noise. It is important to note that an SNR of 40 dB has been identified as an acceptable range for effective damage detection under the conditions tested in this study. Within this range, VMD effectively manages the noise, allowing for clear identification of damage locations. However, when the SNR falls below 40 dB, it becomes increasingly challenging to detect damages, especially in scenarios involving higher road roughness. A comparison between EMD and VMD According to the results acquired in the Results and Discussions section, the damages cannot be detected by implementing the EMD. The instantaneous energies of all modes decomposed by the EMD approach are given in Fig. 10, and it can be observed that the peaks seen in those diagrams do not coincide with the location of the damages. In fact, the EMD method

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