PSI - Issue 17

Paulo Morais et al. / Procedia Structural Integrity 17 (2019) 419–426

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Paulo Morais et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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a)

b)

c)

d)

Fig. 5. Spectral amplitudes of a Fourier transform applied on the vertical channel of a cabin accelerometer: a) bridge; b) bridge equipped with USP; c) railway line over embankment equipped with USP and d) railway line over embankment with no USP.

Fig. 6 shows an alternative display of previous frequency spectrums in a continuous condensed form. Higher spectral amplitudes are shown in yellow and lower spectral amplitudes in blue. Here the evolution of the 2 groups of response peaks can be perceived, specifically the dependence, or lack thereof, on the vehicle speed.