CALMMOON RAIL - THE QUIET RAIL
The rail web noise shielding which has been tested by DB AG and BMVBS and found to be the most effective technology for rail web noise damping/shielding in Germany with an average overall noise reduction of 3 dB.
Since 2014 Deutsche Bahn had shielded their track with Calmmoon Rail.
Bridges
Bridges with open steel supporting structures
Steel bridges with open supporting structures are railway bridges which were developed very economically by engineers in times of reduced resources. These structures were and are optimised for costs and benefits and are thus very functional structures which have ensured safe utilisation by the railways for many decades.
Rail shielding
Calmmoon Rail was further developed specially for the challenges of noise emissions by open steel railway bridges. Calmmoon Rail envelopes the rail at both sides of the rail web and at the bottom of the rail. Thus, the noise emitting surfaces are covered in an optimum manner, leading to a maximum reduction in the noise level generated by the rails.
Track possessions
Calmmoon Rail can be installed easily and very quickly on the rails during normal operations and, if required, can be removed as easily.
Ballasted
Maximum shielding of rail surface
In practice, Calmmoon Rail can be adapted very well and easily to all circumstances at bridges and the track, be it different spacings between sleepers at crossings or cables laid at the rail etc.
Calmmoon Rail is adapted quickly to the situation on site with normal tools.
Cables at rail foot
Cables which pass along the rail foot, for example for train control systems, continue to be fully functional after installation of Calmmoon Rail. These cables are now additionally protected by Calmmoon Rail from inadvertent effects due to maintenance work.
Calmmoon Rail offers additional safety for these elements and thus prevents damage to them.
Shielding of rails in curves
Calmmoon Rail does not affect the track decay rate due to its low mass. Thus, the system ensures that the surface of the rail in a curve is formed and corrugated only by the daily train traffic.
Experience the details of Calmmoon-Rail
- What is Callmoon Rail?
- How do I install Calmmoon-Rail?
- How are the emmison effects?
- Environmental effects on Calmmmoon-Rail?
- What’s about measurements and Approval?
Calmmoon Rail is a rail web noise shielding which reduces the emission of the air-borne noise from rail. The low mass of the elements of this technology of only 4 kg per metre of rail is one the characteristics of this system.
Rail web noise shielding
Calmmoon Rail wraps the rails in elements of thin sheet steel onto which is glued the Calmmoon technology for the reduction of airborne noise energy and the vibration energy of the sheet steel. On this, a sound absorbing foam is attached permanently. Two clip fastenings secure the noise shielding permanently to the rail.
Material handling
The elements which are delivered on pallets in units of 10 sleeper sections are distributed manually along the track to be shielded before installation.
At the same time, the ballast below the rails is removed with ballast forks to a depth of about 10 cm so that the shielding elements and the fastening clips can be installed easily.
Installation of rail web shielding
Then the two shielding elements are brought up against the rail on both sides in the section between two sleepers until they sit at the rail. The clips are fitted one after the other. The clicking of the clips indicates audibly to the staff that the clip is safely and durably installed. The ballast which was removed is now manually returned to its original place. If requested, the rolling marks on the rail are transferred in a permanently visible manner to the Calmmoon Rail elements.
Unrestricted track maintenance
The special clip fastening and the rail shielding components ensure optimum and unrestricted track maintenance with conventional ballast tamping machines, ballast ploughs and sweeping machines.
Maintenance work which is carried out properly ensures the continued optimum effectiveness and long life of Calmmoon Rail.
No effect on the track decay rate
The Calmmoon Rail web shielding has a weight of about 4 kg per linear metre of rail. The Calmmoon Rail technology does not affect the vibration of the rail and thus does not affect the decay rate of the track.
Connection between track decay rate and noise reduction potential
Classic mass spring systems increase the decay rate of the track and reduce the emitted rail noise in this way. To do this, about 25 kg mass is installed per linear metre of rail.
For track with a very good decay rate, the effect of mass spring systems is reduced accordingly. This can be seen clearly from the diagram "Relationship of track decay rate versus noise reduction".
Good rail - high track decay rate
Calmmoon Rail technology has demonstrated in several field measurements that even for high decay rates of the rails, e.g. 8 dB/m in the range of 500 - 2,000 Hz according to TSI, a noise reduction of the overall noise level of 2 to 4.4 dB is achieved depending on the type of train. In these cases, the rail roughness was always lower than that specified by TSI and ISO standards.
If you check the decay rate of 8 dB/m in the diagram "Relationship of track decay rate versus noise reduction" you will see that the possible noise reduction of mass spring systems is in the range of 1.0 to 1.5 dB.
Weather resistance
Test as per ISO 10354-2
The Calmmoon noise suppression sheeting was placed in a water bath, the temperature of which was cycled between 0ºC and 80ºC. One cycle lasted 7 minutes.
Once the specified number of cycles had been completed, the sample was taken from the water bath and the vertical absorption degree was determined as per ISO 10534-2.
A significant temperature change takes place statistically on 100 days per year. 3,000 temperature cycles correspond to 30 years of use.
Result: no effect on the noise damping quality.
Water resistance
The Calmmoon noise suppression sheeting was placed in a water bath.
The sample was taken from the bath after 48 hours, dried and the vertical absorption degree was measured as per ISO 10534-2.
Result: no effect on the noise damping quality.
Various field tests were performed between 2009 and 2015. Corresponding documentation can be found in our documents.
Rail web noise shielding
In this report, Calmmoon Rail is named as rail web noise shielding which reduces the noise directly at the rail and meets the requirements of the new Schall 03 [2012] specifications for the calculation of noise emissions on rail tracks.
Calmmoon Rail reduces only the noise emitted by the rail - and this in an optimum manner. When Calmmoon Rail is used, the quality of the rail noise level is determined only by the rolling stock used. The rail vibrations are not affected and thus their action on the wheel and the action of the wheel on the rail are not affected.
Economic stimulus programme II
Economic stimulus programme II was financed by the BMVBS and implemented from 2010 to 2012.
Deutsche Bahn tested a total of 16 innovative technologies to reduce rail noise. For this purpose, Calmmoon Rail was installed on 40 km of track by DB AG.
The results of the measurements by DB AG showed that Calmmoon Rail reduced rail noise by 3 dB on average. In the same way, the measurements showed that of 5 damping technologies at the rail only Calmmoon Rail met the specifications of Schall 03 [2012] with an average noise reduction of 3 dB.
