Beijing National Stadium

The Beijing National Stadium, known as the Bird's Nest, was built as the main stadium of the 2008 Summer Olympics in Beijing. Its tangled lattice of steel members, which forms both the facade and the roof structure, made it one of the most recognisable stadiums in the world.

Design team

The stadium was designed by the Swiss architects Herzog & de Meuron (Jacques Herzog and Pierre de Meuron, with project architect Stefan Marbach) jointly with the China Architecture Design and Research Group, led by Li Xinggang. The artist Ai Weiwei acted as artistic consultant, although he later distanced himself from the project. Arup were the structural engineers. The nickname "Bird's Nest" was first used by the architects themselves.

Structure

The stadium consists of two independent structures about 15 m (50 ft) apart: a concrete seating bowl and the outer steel frame that wraps around it and spans over the stands. The frame uses about 121,000 tons of steel, all made in China. Twenty-four trussed columns, each weighing about 1,000 tons, encase the inner bowl and carry the roof. The site covers about 204,000 m² (about 50 acres).

The roof redesign

The original design included a retractable roof. It was removed after a roof collapse at Paris Charles de Gaulle Airport led to a review of major projects with complex roofs. The upper roof section was altered so that it still shelters spectators from the weather.

Construction

• Groundbreaking: 24 December 2003.
• Official start of construction: March 2004.
• Completion: June 2008.
• Opening: 28 June 2008.

During the Games it seated about 91,000 people, the largest capacity of any Olympic venue, and hosted the opening and closing ceremonies, athletics and the football final.

Significance

The Bird's Nest shows how roof and facade can merge into one structural system, and how a roof design can be changed late in a project because of safety concerns arising elsewhere.