Construction [20]
Design [20]
Manufacturing [20]
Assembly [20]
Grand opening [20]
Movies
Computer simulation
Assembly of steel construction[Time-laps] Installation site of membrane[Time-laps] Membrane in action
Project presentation
[W. L. Gore & Associates]
Retractable roof, fortress Kufstein Kugel + Rein Architekten und Ingenieure
The inner courtyard can be covered with a retractable textile roof. In good
weather events are to take place under the open skys, in the event of rain
the 2000 sqm roof can be closed in 4 minutes.
Completion: May 2006, Client: Stadtwerke Kufstein
In
the narrow northern Valley of the Inn the fortress of Kufstein had been erected
as a defence fortification during the Middle Ages. Today it attracts a great
amount of tourists. In the 1990’s because of the overgrowing vegetation,
parts of the historic building structure were close to decay. Therefore in
1997 the “Top City Kufstein” was founded to reactivate
the fort and put in on the market. Besides of the gradual restauration, the
businesses food and open air events became established, especially in the
southern courtyard of the Josefsburg.
Simultaniously by the fact of having more and more high
quality events, the risk for ticket cancellations grew because of unpredictable
weather conditions: The result was financial loss. Therefore the idea of
a mobile shelter in the case of rain arose, protecting as big an area of
the courtyard as possible. Further requirements were set by the officials
for landmark sites not allowing any kind of anchorage into the existing fort.
At the same time any new structure was not supposed to interfere with the
visual appearance of the location. To comply with these facts, the designers
developed a delicate, centrical cable structure. A membrane located in its
center can be unfolded during bad weather conditions, similar to a huge umbrella.
Covering a 2,000 sqm area, the umbrella can be opened or closed within 4
minutes.
The bearing structure for the membrane covers a circular
floorplan, consisting at the outside of a polygonal pressure ring, not dissimilar
to a 52 m diameter “bicycle
wheel”, composed of 15 equal segments. In
its nodal points the ring is supported by 15 columns, located at the borderline
of the courtyard just in front of the casemates. Within the pressure ring,
15 upper and lower spoke cables are running in radial direction, connected
by vertical wires to a crescent-shaped geometry. The upper spoke cables are
fixed at the top end of the columns, the lower at the nodes of the pressure
ring, composing a hub in its center. The bicycle wheel is an efficient, highly
prestressed bearing structure, that besides of the wind load, brings vertical
loads only to the foundations. Because of the landmark site requirements
not allowing the columns to be founded on the casemates, 5 of the 15 columns
are constructed as floating columns, suspended by 30 crossing diagonal cables.
At the lower end of the floating columns a circumferential ringcable shorts
the traction at the top of the columns via brackets. The columns together
with the circular thrust ring appear similar to a “tiara”, floating
above the courtyard.