Chemnitz Stadion

Winning competition entry for the Chemnitz Stadion, Germany, 1995, Peter Kulka with Cecil Balmond





The roof structure is based on a spirograph curve, sketches by Cecil Balmond, from his book "Informal", p. 159

Spirograph.zip generates spirograph curves with grasshopper

Balmond's Sigma Code

The Search for the Sigma Code has a dense plot and relies on another imaginary narrator (not a monk this time, but) a boy called Enjil. If you have ever wondered why any prime number is greater than three will, when raised to the sixth power, leave a remainder of one when divided by nine, you will be at home with this book. -- Vanessa Thorpe, The Independent On Sunday - 13 September 1998

You get the sigma code of a given number n like this:
1. Calculate the sum s of all digits of n.
2. If s is smaller then 10, s is the sigma value.
3. Else set n=s and return to 1.
With this definition it is possible to calculate the sigma values of number sequences. The result of some simple sequences are beautiful patterns:

This diagrams you obtain from the Fibonacci and the Pell sequence by using (and modifing) the following script: SigmaCode.zip

Beams on Surface

Beams around lines, aligned normal to surface
Height and width are adjustable

Compare Shigeru Ban's pavillon for the Rice Gallery

BeamsOnSurface.zip

Reciprocal grid, example from Cecil Balmond's book, p. 143