Three Potain tower cranes have been mounted on 10m-tall portal bases to help ease congestion at a busy Swiss worksite.
The 25-tonne capacity Potain MD 560 B cranes were erected on the custom-built, 10m-wide bases to enable easy access for other equipment being used at the Geneva construction site.
In this novel arrangement, the units, which were rented to main contractor Implenia by lifting specialist Stirnimann, have proven to be both strong and compact.
“We are working in central Geneva near the United Nations,” explained Pascal Buffat, regional head at Stirnimann.
“We needed a crane with a compact footprint that could handle demanding loads. We designed the portal base to ensure site traffic could flow freely, so the crane gives us optimal reach and capacity without an encumbering size,” he added.
The portal bases were fitted to the Potain trio at Stirnimann’s Olten workshop before being erected at the congested jobsite. The tower cranes stand at heights of 48m, 68m, and 88m, and are being used to perform the heavy lifting during the construction of an office complex.
The Potain units are working eleven hours per day, six days per week, and are being used primarily to lift formwork and precast concrete structures. The cranes will lift the majority of the 5,600 tonnes of steel and 16,500m2 of glass required for the €200mn project.
Situated between the United Nations building and Lake Geneva, the 25,000m2 development will accommodate approximately 2,000 employees once finished. The office complex is scheduled to be completed by the end of 2015.
