The steel structure of the National Stadium the main venue for the 2008 Beijing Olympic Games stood on its own yesterday after the last jack pad was removed.

"Today is the birthday for the 'Bird's Nest,'" said Hou Zhaoxin, a top expert on the construction of 2008 Olympic projects. "With all the supporting structures removed, the huge skeleton of the National Stadium is able to stand on its own. The 'Bird's Nest' is born!"

The photo taken on September 17 shows an overlook of the Bird's Nest. [Xinhua]

Designed by Swiss architecture firm Herzog & de Meuron, global engineering consultant ARUP and China Architecture Design and Research Group, the National Stadium is located on the North Fourth Ring Road in Beijing.

The main body of the stadium is composed of 24 columns of trusses, which surround the bowl-shaped stands in the stadium. The structural elements support each other and converge into a grid formation, just like a bird's nest with interlocking branches and twigs.

Construction started in December 2003 and the concrete work of the main stand was completed on November 15 last year. On August 31, the steel skeleton was welded together.

The removal of the bracketing structures started on Thursday and was divided into seven steps.

The steel structure of the National Stadium. (Photo: CRIENGLISH.com)

"During the process, 156 jacks were placed in 78 spots, and removal was done simultaneously on three levels the outside circle, the middle circle and the inside circle," said Li Aiqing, chairman of National Stadium Company, owner of the project.

According to Li, the steel skeleton weighs 42,000 tons and can now bear a load of 11,200 tons of the roof and hanging parts.

He said the entire steel structure would be completed by the end of November and the project completed by the end of next year.

With a seating capacity of 91,000, the National Stadium will host the opening and closing ceremonies, track and field competitions and football finals during the Games.

The seat number will be reduced to 80,000 after the Games, when it will be used for large-scale sports events, conventional competitions and non-competition events. The national landmark will offer wide-ranging entertainment and sporting facilities to residents after the Games.

Besides the National Stadium, construction at other Olympic venues in Beijing is also progressing smoothly, officials from the Beijing 2008 Project Construction Headquarters Office said.

Significant progress has been made in the building of 26 of the 31 venues in Beijing; and five other related projects are also under construction.

"According to the schedule, construction on 16 more venues will start within this year two renovation, one temporary and 13 training venues," said Wang Gang, vice-director of the office.

Editor: Yan