USM 4000


Calenberg track bed / sub-ballast mat USM 4000 series (max. length 200 m) is made of synthetic and natural rubber and primarily used at high train speeds and high axle loads up to 250 kN. This series produces an effective reduction in vibration emissions from railway traffic.
The studded mat is used to meet vibration engineering requirements – from ballast protection for reduced ballast bed thicknesses through to efficient isolation of structure-borne sound and vibrations in high speed railway lines as well as adaption of track stiffnesses in transition sections.

The USM series is manufactured using high-grade rubber blends. It has a high mechanical load capacity, is permanently weather-resistant and absorbs virtually no water. It excels thanks to its high electrical insulation resistance and provides drainage on the mat level.

The USM 4000 series is suitable for both ballasted and ballastless track systems.


  • Reduction in stress load on the ballast
  • Increased long-term stability for the track position
  • Reduction in the dynamic wheel forces
  • Reduction in the track and vehicle stress load
  • Potential for reduction in ballast height – important on bridges
  • Reduction in track maintenance costs
  • No replacement required thanks to high fatigue strength
  • Expected service life min. 60 years