Riga Mainz prepares for tunnelling in Berlin

Crane company Riga Mainz used a Liebherr LR 1600/2 crawler crane to help with the unloading and hoisting of a tunnel drill at an underground railway construction site in Berlin, Germany.

The site, which is near the Red City Hall, is made up of a 2 km underground rail network that lies between Alexanderplatz and Brandenburger Tor stations in Berlin. To help with the excavation of the first tunnel the Herrenknecht drill, which is 74 metres long and weighs 700 tonnes, is to be used.

The drill was delivered in separate parts to the site by barges on the River Spree. The LR 1600/2 crawler was then used to lift the components onto land. The crawler was configured with a 72 m lattice boom, ballast trailer, and a counterweight of 350 tonnes. For two nights it worked from the edge of a temporary dock.

Once the pieces had been unloaded the crawler was used to lower the pieces of drill 20 m down into a trench. The heaviest part, the front plate, weighed 135 tonnes.

For each hoisting cycle the crane had to travel backwards by around 30 m and then slewed through 120 degrees to lower the load. The job took over two weeks to complete.

Uwe Langer, boss of the Mainz-based crane specialist, said, "Resetting, removing and refitting the ballast on a ballast pallet would have taken longer than the actual 14 hoisting cycles to move the components.”

The first trains are due to start running on this section in 2019.