PSI - Issue 62

Fabio Micozzi et al. / Procedia Structural Integrity 62 (2024) 848–855 Author name / Structural Integrity Procedia 00 (2024) 000 – 000

853

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Fig. 5. (a) measured midspan displacements (negative downwards) in window #3 and (b) close-up at max peak deflection.

3.2. Frequency analysis The signals of the accelerometer at midspan and the displacement recordings (displacement transducer and video camera) were processed to compute the frequency of the first vertical mode of the monitored span. The obtained results (Table 2) show differences negligible between the frequencies determined from the measurements of the contact displacement sensor, the accelerometer, and the video camera, confirming the good results already obtained in previous studies involving other bridge typologies, e.g., Feng and Feng (2021).

Table 2. Comparisons between the determined first modal frequencies. Window Measure

First modal frequency (Hz)

DT1 (displacement transducer)

3.479

AC1 (midspan accelerometer)

3.479

1

FVB1 (video camera)

3.479

DT2 (displacement transducer)

3.479

AC2 (midspan accelerometer)

3.474

2

FVB2 (video camera)

3.474

DT3 (displacement transducer)

3.447

3

AC3 (midspan accelerometer)

3.452

FVB3 (video camera)

3.452