Dancing towers

The dancing towers in Hamburg’s entertainment district

Hamburg’s inner city is presently buzzing with building activity. Besides in the “harbour city” extensive building projects are being carried out also in other parts of the Hanseatic City. For these projects, several separate placing booms SPB 30 and truck-mounted concrete pumps from SCHWING are used.

In the immediate vicinity of one of the most famous nightlife quarters in the world, the “Reeperbahn auf St. Pauli”, a “slanting” new landmark of Hamburg is presently under construction. Surrounded by “Heiligengeistfeld”, the “Millerntor Stadium” and the “Landungsbrücken” the “dancing towers” of Hamburg are presently rising up on 5,400 m² of ground into the skies of the City on the river Elbe. Designed by star architect Hadi Teherani, the two towers with their 22 and 24 floors and a maximum height of 85 m are intended to remind the observer with their exceptionally “skewed” architecture of a dancing couple. Owner of the building is the Strabag Real Estate GmbH. The contract for the construction work was awarded to Ed. Züblin AG. The total cost for this spectacular new building in Hamburg’s red-light district will amount to ca. 180 million EUR. When the construction work will be completed in the summer of 2012, the towers will make the access to Hamburg’s Reeperbahn look like new. Besides offices and a hotel, the building will also be the new home of the legendary Mojo Club. The upper floor will accommodate a bar, a rooftop terrace garden and a restaurant with panoramic view of the city.

During the full construction period, the Hamburg-based company betonlift GmbH & Co KG will be responsible for the concreting work. Studies performed by betonlift have shown already in the planning phase that the use of two separate placing booms SPB 30 from SCHWING SPB 30 makes sense for this project. With a horizontal reach of 30 m and the very good threading capabilities it is possible to execute the concreting work with the 4-section placing boom in a most effective way. On the “dancing towers” construction site, the placing booms are installed at first on free-standing, modular octagonal masts which are safely fastened to the concrete floor slab by means of cross frames and anchor bolts. When the construction exceeds the vertical of the boom, the hydraulic SCHWING climbing equipment enters into action and ensures that the position of the placing boom can be adapted to the work progress so that smooth concreting can be continued up to the top floor slabs. The conveyance of the concrete is basically be ensured by a SCHWING S 34 X truck-mounted concrete pump which delivers the concrete through a fixed pumping line to the separate placing booms. With its wheelbase of only 4.2 m, the S 34 X is the ideal machine for safe manoeuvring even in cramped conditions on a construction site. The concrete pumpkit from SCHWING and the patented Rock valve have proved their reliability and economic efficiency also in this project. The core walls of the building are concreted with a class C35/45 concrete with a water-cement ratio of 0.46 and a largest grain size fraction of 16 mm. The concrete transport from the mixing plant of the company Holcim Beton und Zuschlagsstoffe GmbH was mainly effected with Stetter truck mixers in the “Light Line” and the “Basic Line” versions.

On account of the changing marginal conditions during this project, a close and confidential cooperation between the equipment user and the equipment manufacturer is a necessary prerequisite for optimal results on the construction site. Franz Syrowatka, who is responsible for the project organization at the betonlift GmbH & Co KG company puts it in a nutshell: “We want to support our customers with the best concrete placing solutions from the technical and economical point of view. The new projects have shown that the use of separate placing booms of the SPB 30 type from SCHWING can fulfil this task effectively and in an optimal way. Although we do have a well-coordinated and experienced team of workers on site it is nevertheless important for us to have access to the expert knowledge of the manufacturer. Not only the service technicians of the local SCHWING-Stetter branch, but also the project experts from SCHWING in Herne are always at our disposal for instant support.”

As far as concreting work on the site of the future 7-storey building of the “EMPORIO” complex at Valentinskamp is concerned, the betonlift company has decided to use a separate SCHWING placing boom of the SPB 30 type for this job, too. In the course of the modernization of the “Unilever Building”, which is classified as an historical monument, the project aims at creating new office space and flats in an exclusive city location. The building is executed as a conventional solid construction with particular importance on a sustainable indoor climate and energy concept.