Novel dampers cut the noise on the rails

Silent Track is a dynamic damper claimed to significantly reduce the noise generated by railway traffic.

Silent Track is a dynamic damper developed by Corus which significantly reduces the noise generated by railway traffic.

A world exclusive, Silent Track is capable of reducing noise generated by the track itself by an average of 5 to 7dB, depending on the form of the track.

10km of tracks will be equipped in Holland following tests on several European networks.

They are the starting point for the future large-scale deployment of the product.

Product Development Manager of Silent Track at Corus, Dave Farrington, explains: "Whilst the environmental benefits of rail travel are well known, we need measures to reduce the noise generated from railway traffic".

"This noise is generated in three principal ways - from the wheel/rail interface, from structures carrying the railway and from rail vehicles themselves".

"Noise can be prevented from reaching the public either by containing the noise - using devices such as screens - or by reducing the noise at source".

Silent Track is a vibration damper made of elastomer and steel which is laid on both sides of the rail web.

Corus has applied the knowhow of Southampton University's Institute of Sound and Vibration Research to develop a solution as yet unrivalled on the market.

This close collaboration has produced Silent Track, the primary function of which is to absorb rail vibrations generated by railway traffic and thus reduce the intrinsic noise.

This system can be used on both new and existing track.

With Silent Track, Corus takes a big step beyond the conventional elastomer vibration dampers now available on the market.

The main advance is in the synchronised use of two steel weights and elastomer, their size and shape tailored for a given purpose.

Thus the Silent Track fits a wide range of frequencies and operating conditions.

Says Farrington: "The main difficulty in developing the damping system was to be able to reduce noise level across the wide frequency spectrum - ranging from around 600Hz to several kilohertz".

"Rail noise is in the lower half of the range - up to around 2kHz - and wheel noise is typically in the higher frequencies".

Silent Track is thus synonymous with tailor-made, and adapts ideally to each operating condition, taking into consideration data such as train type, traffic frequency, rail type and rail fastenings.

The Corus rail division engineers, after determining the acoustic frequency bands in which action is necessary, can apply damping precisely at the appropriate place for maximum effectiveness.

David Benton, Responsible for Silent Track business development says: "At Rotterdam and Twello dampers will be installed in situ but for the Zeeland project the dampers have been pre-attached onto 2.7 kilometres of rail at a welding plant".

"The rail will then be re-laid as part of a renewal programme using standard track renewal techniques".

Benton concludes: "Silent Track was trialled in Holland in 2002 using track configurations that are representative of the type found there".

"Using data from the trials, we have been able to ensure our system is designed for maximum effectiveness on the Dutch network".

"Using our understanding of track behaviour and our modelling techniques, we could easily produce a bespoke solution for any unique track conditions".

Silent Track is a solution adaptable to many situations and its effectiveness is all the more remarkable when the train speed on the rails approaches 100km/h.

This makes the installation of Silent Track particularly appropriate for tracks used by freight at night.

Back to top