The National Indoor Stadium will open to the public for the first time on Wednesday, with the Artistic Gymnastics International Invitational Tournament being the first event held there.

Ordinary audiences will be able to watch the games in the central part of the Olympic Garden and have a closer look at the "Bird's Nest" (The National Stadium) and the "Water Cube" (the National Aquatics Center).

The steel roof of the National Indoor Stadium is 144 meters long from north to south and 114 meters wide from east to west, consisting of 2,800 tons of steel in total. The structure houses a two-way chord-tension steel roof with the greatest span in space in the country. 

Constructing the roof of the stadium posed a huge challenge for builders. After consulting a dozen related experts and holding 26 panel discussions and four months of debates, it was decided that robots could fulfill this task.   

Shen Yongshan, chief commander of the National Indoor Stadium project, said that builders assembled the steel roof on the ground and then the assembled parts would be further assembled together onto the roof by nine robots.
 
The National Indoor Stadium will be an indoor stadium with most advanced facilities and most seats in the capital. Its main function is to organize all kinds of national and international professional sporting events and host large sports competitions and/or artistic performances.

Designers and builders made massive efforts to reduce noise. Experiments showed that their labors achieved expected effects. When a heavy rain is falling outside, it is not audible inside the stadium. Zhang Guoqiang, the project manager, said, "The walls of the stadium utilized nine layers of multifunctional metal complex materials with a thickness of 25 centimeters and successfully resolved the rainfall noise problem that commonly exists in most stadium buildings."

Moreover, they also created special designs to reduce the noise emanating from air-conditioners and cooling apparatuses so as to make the building as quiet and comfortable as possible for future audiences.

(China.org.cn by Zhang Ming'ai, November 26, 2007)