The design for the Olympic Stadium in Beijing looks like a bird’s nest. In reality it is an ingenious structure of concrete ribbons draped over one another. The basic form of a stadium, which has changed little since the Coliseum, is still recognizable, but the aesthetic is totally new. It must be completed in 2008 for the opening ceremony of the Olympic Games.

Bird’s nest
The new National Stadium is located on a gentle rise in the centre of the Olympic complex. It is conceived as a large collective vessel. The stadiums appearance is pure structure. Façade and structure are identical. The structural elements mutually support each other and converge into a grid-like formation - like a bird’s nest with its interwoven twigs.

Membrane
The structural elements mutually support each other and converge into a spatial grid-like formation, in which façades, stairs and the roof are integrated. Just as birds stuff the spaces between the woven twigs of their nests with a soft filler, the spaces in the structure of the stadium will be filled with light material. There are two layers of translucent membranes: an outer layer fills the spaces in the structure of the stadium to make the roof weatherproof and an inner layer acts as an acoustic ceiling inside the roof structure, giving the bowl a smooth and homogeneous appearance. The sliding roof is an integral part of the structure of the stadium. When it is closed, it converts the stadium into a covered arena. With its own structural logic, it is also a grid-like formation that forms a waterproof shell together with the translucent membranes.

Crowd
Visitors walk through this formation and enter the spacious ambulatory that runs full circle around the stands. From there one can survey the circulation of the entire area including the stairs that access the three tiers of the stands. Functioning like an arcade or a concourse, the lobby is a covered urban space with restaurants and stores. The stands are designed without any interruption to evoke the image

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