Planted mountain path: filigree work with steel beam weighing tons

A lot of dexterity and precise preparation were required for the next milestone of the bunker raising! Dipl. Ingenieur Jens Siggelkow and his team have now mounted an approximately 30-meter-long and 35-ton lattice girder directly below the bunker collar on the west facade. Millimeter work with a mighty steel colossus!

30 meters long, weighing 35 tons – a steel truss for the mountain path to the Stadtgarten has now been installed on the bunker’s west side.

Two truck-mounted cranes raised the imposing lattice girder and pulled it up to a height of around 35 meters in order to maneuver it into the boreholes and receptacles on the outer facade. A delicate operation during which the two crane operators had no direct eye contact and could only communicate by radio. After about four hours, the challenge was met: The steel girder was bolted between the two flak towers with several threaded rods, each two to three meters long. Closing the gap is another big step on the coming way up to the new public city garden, 58 meters high above the Hanseatic city.

Final touches to the prepared drill holes.

The upcoming planted mountain path will be an essential part of the experience of the Green Bunker St. Pauli. Once completed, the approximately 300-meter-long, 422-ton, five-meter-wide climb will start at ground level on the north side of the bunker. To do this, 24 steel support arms, each weighing around 5.5 tons, will be attached to the outer facade with several threaded rods, each two to three meters long. The ground foundation of the later path is formed, among other things, by approx. 20 cm high prestressed concrete slabs with a further 24 cm high superstructure. On top of this, in turn, the substrate for the greening will be applied. The first prestressed concrete slabs can already be seen on the south side of the bunker. In addition to the planted mountain path, visitors will in future be able to reach the Stadtgarten via the two newly constructed outdoor elevators on the east side of the building. The free access is barrier-free.

Here, two truck-mounted cranes carefully lift the steel hulk.

Text/Photo: Frank Schulze Kommunikation