Thursday, 7 May 2009

Zarzuela Hippodrome – Eduardo Torroja (1935)

L - Eduardo Torroja, Zarzuela Hippodrome A thin-shelled concrete roof for what is now a seventy-five year old stadium near Madrid.  The concrete is 5 1/2 inches thick at the supports and just 2 inches thick at the edges.

The roof form itself is generated by “hyperboloids of revolution,” making each segment easy to analyse and distributing the forces evenly through each of the shell surfaces – which is what allows this thin surface to support a 42 foot cantilevered span.


  1. PC, is it a prestressed cast shell or ferro-cement?

  2. Concrete is not very good in tension and it is brittle. Amazing how good the design must be to do this. Personally I'd have done it in steel and clad it. Call it peace if mind.


  3. PC said...
    hyperboloids of revolutionThe surface can also be generated by an absolute Sine or Cosine function, ie, positive of a function, such as:

    F(x) = |Sin(f*x)|


    F(x) = |Cosine(f*x)|

    where 'f' is the pitch or frequency of the hoops and 'x' is the distance/length of the entire roof.

  4. The curvature I described above, is a sort of tongue in cheek that I usually describe some of my relatives who've got body shapes like absolute Sin and Cosine function. They think its a good thing when I tell them that they have peculiar body physiques which look like trigonometric functions. I have always encouraged them to do exercise by joining a gym, because us Islanders eating lambflaps will give us trigonometric type body physiques.

  5. Richard Toy's pavilion at Mt Albert Grammar School is based on this work.


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