Areas of use for sub-ballast mats

Sub-ballast mats are primarily used on surfaces covered with ballast in railway track systems in structures such as bridges and tunnels to prevent ballast wear or to protect structure layers in the interface between ballast and concrete or steel. The mats are also used for vibration insulation and structure-borne sound control in the rail system track structure. Their areas of use include rail route sections close to vibration- or sound-sensitive buildings and structures and sections where certain requirements are made on the rigidity of the track structure.
Calenberg sub-ballast mats are suitable for all types of railway operation.


Vibration protection and ballast conservation

There are different types of track structure – ballasted track and ballastless track – in which different components are used to prevent wear and possibly provide vibration protection. Sub-ballast mats are suitable as a protective measure against vibrations and sound transmission caused by passing trains.

Sub-ballast mats are laid across the entire surface directly beneath the ballast bed to provide elastic decoupling plus protection for track components. Sub-ballast mats, for example, protect ballast from destruction so that the track does not need to be tamped as frequently. A stable track position can thus also be guaranteed and the substructure’s load-bearing capacity is maintained.

The elastic sub-ballast mats retain their stability even when subject to long-lasting continuous loads and under different climatic conditions, thus contributing to track system maintenance cost efficiency and a long service life for the ballast bed.

Made of bound rubber fibres or granulate, Calenberg’s recyclable sub-ballast mats are designed in different versions for different axle loads and are used for all types of rail systems from tram, light rail and underground networks through to freight transport and long-distance and high-speed rail networks.

All Calenberg sub-ballast mats conform to DIN 45673-5 and will soon be extensively tested in compliance with the new EN 17282 standard.




Short description

The two-layered product consists of 100% recyclable elastomers and is lined with a geotextile (GRK 5) on its upper surface. Ciprotec helps to reduce environmental impact and conserve resources. The elastomer layer structure made of bonded rubber fibres and the different mat thicknesses combined with the geotextile protective layer help any conventional ballast track to achieve the required elasticity.


  • Reduces vibration and structure-borne sound
  • Stabilises track structures
  • Conserves ballast
  • Reduces dynamic wheel forces
  • Cuts track maintenance costs
  • Long service life and easy to install
  • Recyclable materials which can flow back into the recycling loop

Description, application

About 1,500 mm wide, the mats are used for all railway system types and axle loads up to 25 t, primarily for ballasted track. The product gives efficient protection against vibrations and structure-borne sound in areas surrounding tracks. What‘s more, the ballast is also protected effectively against wear.

The mat comprises an insulating layer made of bound rubber granulate, which is covered by a wear-resistant solid rubber top layer. This top layer protects the insulating layer from potential mechanical damage caused by elements such as ballast.

The top layer together with the solid rubber lower layer also make the mat water-tight and weatherproof, thus contributing significantly to the product’s optimum robust design and long service life.