Issue 70

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

Y Y Y , ut t r     

(58)

where, Y ut  , Y t  , and Y r  represent beam acceleration under the trailer axle, absolute acceleration of trailer axle, and relative acceleration between trailer axle and beam, respectively. An illustration of these parameters is given in Fig. 9. The beam acceleration under the trailer axle is analyzed through both the EMD and VMD in the following bridge damage scenarios.

(a)

(b)

(c) Figure 9: (a) Beam acceleration under trailer axle, (b) Absolute trailer axle acceleration, (c) Relative acceleration between trailer axle and beam.

R ESULTS AND DISCUSSIONS

n order to investigate the applicability of the proposed methodology in identifying damages, different damage scenarios are examined according to Tab. 3. All signals are collected at 5 m/sec velocity. EMD was used to analyze damage scenarios (P2, A2, B2, C2) to find the location of damages. The number of modes extracted by EMD is 7 modes in the P1, B2, and C2 scenarios, and 8 modes in the A2 scenario. The location of the damage is not evident in any of the instantaneous energy diagrams, as shown in Fig. 10. The VMD approach's performance to spot damage will be described further below. I

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