TUNNEL DOOR WITH CONCRETE CORE REVOLUTIONIZES TUNNEL SAFETY
March 2023
Kirchdorfer Group, Elkuch Group and Biprotec GmbH revolutionize the safety of rescue doors in tunnel construction. A concrete core in the tunnel door reduces deformation in the event of fire and increases fatigue strength – the durability under alternating pressure and suction loads.
The door panels with a concrete core are produced by Kirchdorfer Concrete Solutions, the precast concrete division of the Kirchdorfer Group, and completed by Elkuch to form a complex tunnel door with a frame. They will be used for the first time in the Great Belt Tunnel (Slagelse – Nyborg), where the first 60 double-leaf tunnel doors will be installed in summer 2023.
The seals are an important prerequisite for preventing burning or smoking through into the safe rescue tunnel in the event of a fire. These remain intact for longer thanks to the reduced deformation of the innovative solution with concrete core! Previous tests have confirmed a fire resistance classification ofEI2120. This value confirms that the room closure (E) and thermal insulation (I) are still fulfilled at 1050°C and a dwell time of 120 minutes. Gerhard Rinnhofer, F&E Kirchdorfer Concrete Solutions, assumes that “the limits have by no means been reached here.“
Biprotec Managing Director Robert Binder “sees the durability in terms of corrosion as a further advantage of the tunnel door with concrete core developed together with Kirchdorfer Concrete Solutions.”

for 120 minutes without any problems (=EI2120).
© Kirchdorfer Group