"A special feature of the 151-room Skypark hotel that overlooks the Berlin-Mitte district, is that it exploits the inner-city potential of adding another storey," says Reiner Dinse from the Hannover office of BKL Baukran Logistik GmbH. "The hotel's modular design requires large wood modules, each of 20 sqm and weighing about 7.5 tons, to be lifted over a distance of 75 meters. Not many cranes can handle such a Herculean task,” he adds.
Special steel construction
Given the challenging requirements of load capacity and radius, the construction team picked the 21LC750 flat-top, one of Germany's most powerful hire cranes. With its 80-metre-long jib and a PowerLift system, the model is the right machine for the job of lifting the modules from the street 20 meters below, to the above-ground park deck.
As the bearing capacity of the car park roof is insufficient for such an exceptional load, the building contractor MQ Real Estate teamed up with the crane specialists at BKL Hannover and a steel constructor to design a special 16.5 x 16.5-meter steel substructure to transfer the load, assembling the crane on its 10-metre folding cross base.
Time-efficient assembly The BKL specialists settled on a 500-ton machine from their fleet of mobile cranes to assemble the Comansa tower crane and lift its (approx.) 24-ton cross base. The Ring-Center's central location on Frankfurter Avenue, one of Berlin’s main arterial roads, called for a tight schedule, not just to assemble the 21LC750 crane, but also to set up and dismantle it. The BKL project team’s synchronized plan to transport and deliver the crane parts to the site to install the steel substructure and the construction crane was completed in just five days.
The 21LC 750 will complete lifting of the 151 room modules, which are fully equipped apart from the moveable furniture, by August 2018.