Issue 62

P. Ghannadi et alii, Frattura ed Integrità Strutturale, 62 (2022) 460-489; DOI: 10.3221/IGF-ESIS.62.32

The utilized two-step methods are classified in Fig. 8. A large number of two-step methods are related to the combination of modal strain energy-based methods and PSO.

Mode shape curvature + PSO

Modal flexibility + PSO

Other methods + PSO

Wavelet transform + PSO

Modal strain energy + PSO

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Figure 8: The classification of different two-step methods by number of publications

As mentioned earlier, objective functions and optimization algorithms play a crucial role in identifying accurate results in structural damage detection problems. Fig. 9 and Fig. 10 illustrate the classification of utilized objective functions and different variants of PSO by the number of publications. As shown in Fig. 9, the most utilized objective functions are based on natural frequencies, natural frequencies + MAC, and natural frequencies + mode shapes, respectively. Fig. 10 presents four algorithms, including PSO, UPSO, IPSO, and PSO-NM, which have repeatedly been applied to detect structural damages.

Natural frequencies Natural frequencies + MAC Natural frequencies + Mode shapes Modal flexibility MDLAC Mode shapes FRFs Time-series Modal strain energy Natural frequencies + Modal strain energy + MAC Natural frequencies + NFVAC Natural frequencies + Modal flexibility MAC Modal strain energy + MAC Natural frequencies + Displacements Natural frequencies + Modal strain energy Natural frequencies + Modal strain energy + Modal flexibility Modal curvature Modal curvature + Modal strain energy Cornwell indicator Transmissibility

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Figure 9: The classification of utilized objective functions by the number of publications.

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