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 15: Normalized instantaneous energy of IMF extracted through VMD for cases (a) B1 ls , (b) B2 ls , (c) B3 ls , (d) C1 ls , (e) C2 ls , (f) C3 ls .

Effect of velocity In this section, the effects of various TT speed on damage detection are investigated. It is evident from the simulation results that the damage location can be determined at varied speeds. This is illustrated in Fig 16. The normalized instantaneous energy of A2, B2, and C2 damage scenarios is shown in this figure. Different velocities ranging from 2 m/sec to 30 m/sec are investigated. The noise in the IMF's normalized instantaneous energy is more pronounced at low speeds, e.g. for 2 m/sec than the higher speeds.

(a) (c) Figure 16: Normalized instantaneous energy at different velocities extracted through VMD for cases (a) A2, (b) B2, (c) C2. Based on the simulation results, the VMD method is effective in detecting damages across a wide range of vehicle speeds. Specifically, within the range of 2 m/sec to 30 m/sec , damage detection remains reliable. This demonstrates the robustness of the VMD approach in varying operational conditions. However, at the lower end of this speed range, increased noise levels can introduce more fluctuations in the normalized instantaneous energy, although damage locations are still discernible. Effect of mass ratio The examination of damage detection under various trailer masses is also examined. Tab. 5. illustrates the different masses associated with m t0 and m t1 in different cases. Fig. 17 displays the impacts of mass when the TT passes through the A2 damage scenario. (b)

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