In Germany the DB Netz AG in collaboration with DB Systel created a specification for a cable duct system in glass fibre-reinforced plastic. As the system had to be in- stalled in the ground and elevated it made sense to work with the already well known glass fibre-reinforced plastic (GRP). Due to rough and difficult terrain conditions or tight spaces, it is not always possible to install conventional concrete cable duct systems. In such cases the EINLWL- system is an option. The EINLWL-system must protect and be able to carry one fibre optic cable with 60 fibres.

This cable corresponds to a diameter of 25 mm. The cable duct system must be designed for an elevated and in the ground installation. The specification provides a minimum distance between the supports of 2 metres. The present system was laid out for a 3 metre span. Therefore a structural analysis was done and rechecked by an inspecting structural engineer. Practical tests were done together with DB Systel and the installer - company Andreas Mühlbauer GmbH in Saalfeld according to the specifications of DB Systel. In early 2011, a first test track of 8 km was installed for the German Orlabahn.

• 3 metre span snap-in lid easy to install
• usable cross section 53 x 56 mm
• EINLWL GRP-cable duct system with glassfabric reinforcement manload 140 KG
• few parts

The installation of the EINLWL system is highly efficient. The system consists of 1 galvanized steel square tube, 1 galvanized steel connection plate, GRP cable duct base and lid. The elevated system only needs one bolt every 3 metres. The connection plate is bolted to the square tube. The 3 metre long GRP cabled duct base is only inserted into the connection plate. The 3 metre long GRP lid snaps in the GRP cable duct base without any additional fixings. The installation in the soil is fixed with 2 soil nails. This allows the use of very few parts on the construction site, therefore achieving a high operating efficiency. Due to the 3 metre span, one third of ramming and connections plates can be saved.

Preproduction 

series release DB Netze TM 2010-342 I.NVT 2 zu Ril 416 859 860

Fire behaviour

K 1/3 mm according to DIN 53438 part 2 V0 according to UL 94, S4 according to DIN 5510-2 Halogenfree in accordance with IEC 61249-2-21