Diagnosis: Multiple challenges – 13 WOLFF cranes construct a new US hospital in Weilerbach

26.01.2024 | Press Release

“Even before the crane foundations could be planned, numerous bureaucratic hurdles had to be overcome,” says work planner Daniel Rüttinger, who is responsible for process planning and construction operations at Ed. Züblin AG. Because the construction site is located in the flight path of Ramstein Airbase, every building construction site and mobile crane requires an aviation permit from the German Armed Forces Aviation Office and must also be equipped with special lighting.

Surprises underground

Another challenge in the construction preparation was the foundation of the cranes. “Due to the highly heterogeneous subsoil, consisting of several soil layers, exploratory drilling was carried out at each crane site,” explains Daniel Rüttinger. The buoyancy caused by rising groundwater, existing pipes, and the compatibility of the concrete foundations with naturally occurring radon in the ground also had to be taken into account when laying the crane foundations.

In order to cover all sections of the building, some cranes had to be positioned at particularly low points, where they were set up on foundations up to 2.4 meters high. Because these areas will be backfilled with soil during construction, the lower tower sections were encased in crane shoring. This allowed the surrounding building foundation components to be erected, the working area to be backfilled, and the crane to be completely dismantled again later.

A combination of classics and new additions

ARGE is deploying a WOLFF 8033.16 Cross, a 7534.16 Clear, a 7032.12 Clear, three 6031.12 Clear, three 6031.8 Clear, two 5014.6 City, a 262 SL as well as a 6522 FL 12 at the construction site. The cranes have lifting capacities of between 6.0 and 16.5 tons and peak load capacities of between 1.8 and 7.0 tons. The tallest cranes stand on towers almost 70 meters tall.

“Ten WOLFF cranes come from the Züblin Group fleet,” says Thomas Odenbreit, Wolffkran Sales Executive Germany. “As our long-standing business partner, we are delighted that Züblin has once again acquired three WOLFF cranes (WOLFF 6031.12, 7032.12 and 7534.16) for this outstanding project. It is also pleasing to see a true classic supporting the pack. The WOLFF 262 SL was built in 1989 and has been part of the customer portfolio for 34 years. This is ‘living proof’ of the durability of a WOLFF,” says Thomas Odenbreit. 

Until the end of 2024, the cranes will be moving reinforcement and formwork, semi-prefabricated parts, concrete buckets, and prefabricated staircases weighing up to ten tons. Five of them will remain on the construction site after completion of the structural work to support the further construction of the building. The first patients are due to be treated in the new building by the end of 2028. The hospital is intended for wounded US soldiers from combat missions, but also to provide care for more than 200,000 US-military personnel, civilian employees of the US Department of Defense and other American authorities and their families in Europe.

Züblin and Wolffkran are currently working on other major construction sites, such as several sub-projects of “Stuttgart 21.”