Anti-vibration tracks – Hybrid embedded tracks
Continuously embedded rail and discrete fastening systems are combined in a hybrid resilient track system in order to combine the advantages of both systems:
- low radiated noise level;
- good vibration isolation;
- possibility to replace the rails in a short time, under operating conditions.
The first wheel-rail resonance of this system can be tuned to 40 Hz or even 30 Hz, depending on the selected rail pads.
This parameter is critical for vibration isolation: a lower wheel-rail resonance frequency produces better vibration isolation. For comparison, the corresponding resonance frequency of a ballasted track or of a conventional embedded track is about 60 Hz.
After alignment of the track, the concrete slab is poured in one or more phases. The rail trough is filled with the rubber grouting and an elastic joint is put between the railhead and the road surface.
Vibration measurements in exploitation have shown a reduction of 18 dB of the vibration levels generated along the track during tram passages.