October 2002 -- Design competition
In October 2002, BOCOG engaged architects worldwide in a design contest. After six-months of fierce competition, the consortium formed by Herzog & de Meuron (Switzerland), Ove Arup (UK) and China Architecture Design & Research Group managed to beat out the competitors with a design for a stadium that would resemble a bird's nest, which is now the nickname of the stadium.
December 2003 -- Groundbreaking
Ground was broken on Christmas Eve in 2003, and construction started in March 2004, though the project would be suspended in July 2004 to allow for design modifications tailored to the concept of "economical Olympics."
November 2004 -- Revision of design
Maintaining the original design concept, the revised proposal resulted in 22.3 percent less steel used and a 13 percent reduction in membrane material by abandoning the convertible cover and enlarging the opening in the roof.
August 2006 -- Steel structure welding completed
Welding of the steel structure was completed on August 31. Over 100 skilled welders started their work on August 23, using a total of 2,000kg of welding rods. The whole steel structure weighs 42,000 tons.
September 2006 -- Removal of the steel structural truss
The removal of the steel structural truss of the National Stadium was finished successfully at 11:10 a.m. on September 17. It took three days, from September 14 to September 17, to remove the structural truss of the National Stadium. The successful removal of the structural truss of the National Stadium was an indication that Chinese experts and builders had solved all difficulties in the construction of the stadium's steel structure.
June - November, 2007 -- Membrane covering installed on Bird's Nest
The membrane covering of the Bird's Nest is curved and double-layered, providing decorative, soundproof, wind-proof, rain-proof, and even UVA protection to its already impressive body.The outer layer is made of ETFE panels and the inner layer consists of PTFE material.
November 2007 -- Interior decoration
Decoration of the interior started in November 2007, after the completion of the concrete, steel and membrane structures. In December, ornamental trees were planted around the Bird's Nest.
January 2008 -- Seats installed
All 80,000 seats had been installed on the stands as of January 28, 2008. Made of modified polypropylene, the seats have shown excellent performance in flexural and impact strength tests, and they are customized to offer comfort to the spectators. The colors of the seats will remain fade-resistant for three years under ultraviolet radiation.
February 2008 -- Illuminating facilities tested
The illuminating facilities were put into operation on the night of February 4, 2008. The red lights and grey steel structures of the project make up a splendid addition to the capital city's nightscape.
April 2008 -- Synthetic track installed
The stadium was covered with 140,000 sq. m. top quality synthetic track surfaces from Italy on April 12, 2008.
May 2008 -- Mobile turf installed
The Bird's Nest turned green on May 14, 2008, after workers and soldiers laid down 7,811 square meters of mobile turf. The process took 24 hours. Now the Bird's Nest is ready for the Olympics.
posted by midori mizu