The 2008 Beijing Olympics will have the largest and most unusual swimming centre ever built, putting real pressure on designer Arup to use the most cutting edge tools available.
The so called 'Water Cube' will house the pools for the Olympic swimming and diving competitions, along with seating and facilities for 17,000 spectators (NCE 9 December 2004).
The structure was inspired by the shape of an array of soap bubbles and is highly repetitive and buildable while appearing random and organic.
To take advantage of this repetition a comprehensive 3-D structural model was created and imported directly into the Strand7 modelling package, produced by Sydney-based Strand7 Pty.
Using Strand7 Arup was able to make significant savings through optimising the structural design - ensuring that the weight of the building could be kept to a minimum without The Strand7 finite element model of the Water Cube sacrificing strength.
Each of the 24,000 beam elements, subject to 200 load combinations, was checked at five points against 13 different equations in the Chinese structural code.
Every member and node had the potential to be different, so considerable optimisation processing was required.
But all this optimisation was automated within Excel, so it did not require particularly sophisticated computer programming or languages.
Using the API, a single iteration of the entire Water Cube design optimisation process took only one hour.
Arup took advantage of the Strand7 Sparse Solver to facilitate this. This enhanced solver allows very large models to be solved more quickly than other solvers commonly found in structural analysis software. The complete optimisation process took about 25 iterations and led to a saving, which reduced the weight of the Water Cube to a very light 100kg/m 2. Strand7 was also used to perform seismic design, with Arup making use of the software's capability to take site specific seismic time histories and simply create equivalent spectral curves.
The package was also used for complex elasto-plastic analysis of the beam connection details.
The accuracy of the results of these non-linear analyses was confirmed by full scale testing.