Complex crane operation in the heart of Vienna – three WOLFF cranes build a new department store on the "Mahü"

10.07.2023 | Press Release

Wolffkran planned the crane concept so that only the WOLFF 8033.16 was erected with a mobile crane. This crane was then used to erect the WOLFF 7532.16 Cross, which in turn was used to erect the flattop WOLFF 6023.8 Clear. Thanks to this, the use of a mobile crane could be reduced to a minimum on the busy shopping street. "For the assembly of the roughly 14-tonne jib of the WOLFF 7532.16, our team had to calculate an overload hoist for the WOLFF 8033.16 since the crane was statically reaching its limits at this point," reports Zeljko Tenjovic, Managing Director of Wolffkran Austria GmbH.

Likewise, the Habau team around Kurt Mörth, Site Manager for large-scale construction projects, faces static and physical space constraints. "There is a high density of buildings all around. Neighboring buildings may not be slewed over at all, and the areas frequented by pedestrians may not be slewed over with load," says Mörth. "Furthermore, pipelines installed in the surrounding area and the existing underground parking garage limited the possible locations for the crane."

Working in close coordination with Wolffkran, the decision was made to position the WOLFF 8033.16 on the edge of the construction field facing the Mariahilfer Straße and the two smaller WOLFF cranes on the foundation anchors inside of the approx. 6.500 m2 construction site. The cranes were installed at the beginning of 2022 and utilized for transporting concrete, formwork, and reinforcement for the in-situ concrete shell.

Saving the most difficult for last

Yet the greatest challenge awaits the Wolffkran team in the coming fall when the last of the three cranes on site is scheduled for dismantling. With the WOLFF 7532.16 and the WOLFF 6023.8 standing in the middle of the building they are constructing, they cannot be dismantled using a mobile crane. Therefore, the WOLFF 7532.16 will first dismantle the WOLFF 6023.8, and afterwards, it will be dismantled by the 8033.16 standing some 60 meters away. Consequently, the 13-tonne heavy counter jib of the 7532.16 will have to be split into two parts. "To handle this, we need to release the bracings of the counter jib at the tower top and support the remaining jib section with special supports towards the crane tower before this component can then also be taken down," says Zeljko Tenjovic, explaining the extraordinary endeavor.

"A competent solution for every challenge"

"Apart from the reliability of the crane, one reason why we have been collaborating with Wolffkran for many years is the Wolffkran team's long-standing experience. They find a competent and pragmatic solution for any challenge – big and small," says Kurt Mörth. "When a hoist was damaged during a rope replacement, the Wolffkran team procured the most readily available spare part – from England."

Habau and Wolffkran are collaborating on several projects, including the Harbor Portal in Linz and the Vienna Twenty Two residential quarter in Vienna. They also worked together on the Bruckner Tower in Linz. The Lamarr project is anticipated to be finished by 2024.