Crawford Architects submitted a concept design for the new National Stadium in Tokyo for the Japan Sport Council’s bid for the 2020 Olympic Games in September. The winning entry of this international call for submissions was recently selected.
Our concept is derived from a sea urchin “test” (shell). While the symmetry is not obvious in the spiny form of the living animal, it is easily discernible in the dried test; a fivefold symmetry defined by white bands where the sea urchin’s rows of tube feet are located. These five bands are represented on the stadium by the five vertical super trusses supporting the roof and aperture structure. The operable portion of the roof is a mechanical iris diaphragm formed by five rotating leaves further reinforcing the significance of the number five in Japanese culture and philosophy.
The roof closes around the Olympic Torch which is suspended in the center of the aperture below the roof structure. When the roof is open, the five leaves of the mechanical iris nest in under the fixed roof. The fixed portion of the roof and the operable leaves are clad in translucent ETFE ensuring that the stadium interior is bright and inviting under all weather conditions.