The Solid Slab Track „System NBU“ is equivalent in its construction and application to the “Solid Slab Track” systems, which have been used since the 1970’s. Since then the Deutsche Bahn (German Railways) and the civil engineering industry have been developing and continue to develop different kinds of ballast free railway systems.
Compact systems without sleepers have the following characteristics:
- Rails resting on single fastenings
- Concrete as a long lasting slab having tight tolerances
- Laying the rails complete with fastenings
- High degree of precision when laying the track
- Levelling plates to maintain tight tolerances
- High technology surveying instruments for precision in track laying
- Use of rapid hardening grout (jointing compound)
- Environmental impact is considered in the planning and construction
The “Solid Slab Track System NBU” is a continuous fabricated concrete slab supplied with a concentric placed reinforcement, which provides the System with a high factor of safety redundancy. This kind of construction in conjunction with the structural designs basics of the original systems is used in a modified form in the NBU–System.
The further development of the original systems was carried out with the following objectives in mind:
- Simplification in construction
- Maximising the cohesion between concrete slab and rail fastening
- Simplification and rationalisation of the installation technology
- Greater flexibility during construction with regard to weather conditions
- Minimising maintenance expenditure
- Improving techniques for repair work and in the case of average
The patent of the „Solid Slab Track System NBU“ is registered worldwide. Use of the system requires permission from the NBU company and the engineering company assisting with the development of the system.
A sample was examined by the department for the construction of road and rail communications at the Technical University of Munich. The purpose of the examination was to prove the cohesion of the rail fastenings with the load bearing concrete slab.
In Test Report Nr. 2037 of 19.08.2003 it was confirmed that the new form of construction developed by NBU fulfilled the high quality standards of German railway systems as listed in paragraph no. 2 below.
With regard to the cohesion between the concrete slab, grouting and fastenings supports, no damage or disturbance was found even after 7,5 million manipulations had been applied.