Secret released of the new design of Bird's nest
The office of the Beijing "2008" project construction headquarters recently released the "100 questions manual on scientific and technological innovation of the Olympic project", which details how the National Stadium, known as the "bird's nest", was built.
According to the manual, the "bird's nest" is 333 meters long from north to South and 297 meters wide from east to west. The highest point of the metal gymnasium building is 69 meters, which is equivalent to the height of 23 floors.
The steel structure of the "bird's nest" is divided into several types of components, such as column base, truss column, top main truss, facade substructure, top substructure, and facade stairs. The steel structural members are transported to the site after being processed by units in the processing plant. They are assembled on the ground by welding. The assembled structural members are hoisted in place by large cranes and welded at high altitudes. The main structure of the top surface is placed on 78 temporary support towers, and the high-altitude installation is completed in the way of "segmented high-altitude bulk". After the installation and hoisting of all truss columns, top main trusses, facade substructures, and steel structure facade stairs are completed, and the four closure lines (128 closure openings) are closed under the designed closure temperature to connect the stadium steel structure to a whole.
After the steel gym building is closed, the method of "hydraulic lifting to remove the support point cushion block" is adopted to unload the steel structure step by step in 7 large steps and 35 small steps. The 78 units of temporary support tower support points are separated from the steel structure to achieve the purpose of removing the support tower. After the support tower is removed, the top substructure will be installed. By the end of November 2006, all the top substructures will be installed and the bird's nest rigid steel building will be built.