An important extension has been carried out for the Panofsky building of the Chemnitz Clinic, Germany. A new helipad for rescue helicopters will enable faster and improved care for the seriously injured. Hot dip galvanized steel was used for the structure of the helicopter landing deck, which permanently protects the structure from corrosion and provides the required fire protection.
The new roof landing pad at a height of 18 m was designed to meet the latest safety standards. Its square, heated landing area allows flight operations 24 hours a day. It provides a take-off and landing area of 21 m and can be used by helicopters with a maximum take-off weight of 6 t.
The Panofsky building was erected as a prefabricated reinforced concrete skeleton in 1980 and renovated in 1995. As part of the renovation work, an atrium over 2 floors was retrofitted in the centre of the base area. As a result, sufficient load-bearing reserves for the construction of the helicopter landing deck were only available within the inner supports of the existing building. The load-bearing grid of the landing deck had to coincide with that of the existing building. This arrangement also helped in that the elevated construction had to minimize air turbulence caused by wind at the eaves edges.
In order to fit within the site conditions, it was important to have a relatively light, modular and low maintenance solution. A galvanized steel structure was able to meet all of these requirements.
In terms of construction, the preservation of the atrium and the light domes posed a particular challenge, as this required a defined fire resistance of the main load-bearing members of the landing deck. The Architektur- und Ingenieurbüro Sünderhauf, commissioned with the planning and execution of the landing deck, first tried to verify the supporting structure without fire resistance in accordance with building regulations, which was not successful with sufficient certainty. For this reason, the realization of a fire resistance of 30 minutes by coating or cladding was planned.
On further investigation and recalculation taking into account hot dip galvanizing of the steel, it was proven within the overall fire design calculations that the section sizes used would provide fire resistance of 30 minutes. The use of hot dip galvanizing made it possible to dispense with passive fire protection measures and thus save costs and resources.
Photos © Architektur- and Ingenieurbüro Sünderhauf
