This is one of my favourite staircases. Structural and design genius.
A white concrete cantilevered staircase that challenges metal for slimness - Hans Exner, Ramboll Engineers and Bendt Aarup - CRC (Compact Reinforced Composite) Technology.
"CRC is a special type of [steel] fibre reinforced high performance concrete developed in 1986 by Aalborg Portland in Denmark". "The CRC binder is more expensive than cement and the steel fibre content also leads to a higher price for CRC. On the other hand elements are typically one-third the volume of conventional concrete...the price for CRC has been equivalent to alternatives in steel or concrete. Obviously in cases where the architect chooses very special solutions this also requires a higher price, but in these cases it has little to do with the price of materials, but more to do with the price of formwork and production costs." However the "challenge of utilising a different type of material in a manner that leads to savings in the total cost has been met by a number of Danish architects...just like the spiral staircase at Tuborg 15."
Concrete Elegance One- A series of architectural presentations given at the Building Centre by leading designers, innovators and manufacturers of concrete. The Concrete Centre 2006, RIBA Publishing.