Rail vibrations: data analysis and FE modelling with applications to signalling equipment

The paper aims at comparing the behaviour of a number both different and similar track formation in order to highlight any differences in the vertical dynamics which are the most relevant found in service. Then the spectra of vibrations encountered during revenue service in the same situations are analyzed, showing the differences with the spectra described in the standards. A simplified model of the vertical dynamics of a track is therefore shown where modifications are introduced, including the absence of railpad (direct fastening of the sleeper to the rail), an abnormal or absent stiffness of the sleeper support (“hanging sleeper”), and an extra mass loading. As aforementioned, all these conditions may be found in an in-sleeper point machine.