Beijing National Stadium, also alternately referred to as Beijing Olympic Stadium, or the Bird's Nest, is the centerpiece of the city of Beijing's Olympic complex, aka the Olympic Green, located on the northern outskirts of the city. The Bird's Nest, as we will call it here for the most part, was designed by the Basel-based Swiss architect company, Herzog & De Meuron, and was realized in collaboration with the British engineering company, Arup (whose founder is Danish-British Ove Arup), and China Architecture Design and Research Group (CADG), whose lead architectural designer at the time was Li Xinggang, who now serves as the company's vice chief architect. The design legacy of this unique stadium is expected to be to Beijing what Sydney Opera House has been to the city of Sydney, Australia - a metropolitan as well as a national landmark (for example, Time Magazine's 2008 panel of architectural judges declared the Bird's Nest to be among the 100 most influential architectural designs of all time).
The Bird's Nest, in its most reduced terms, represents countless tons of concrete and 110,000 tons of steel, including the steel that went into the parts of the building that either supports the base of the "nest" (which extends far underground), forms the steel, nest-like roof, or which plays a non structurally-supportive function, such as the network of interlocking steel bars that fixes the seats and thus reduces the likelihood of collapse, a problem that has been on the rise in recent years in older stadiums (note that the exposed "nest" itself consists of "only" 45,000 tons of steel).
The Bird's Nest essentially consists of two separate structures - an outer steel framework (the "nest") and a concrete "bowl" into which the seats are fixed - separated by a free space of some 50 feet. One might reasonably contend that the stadium consists of three structures, if one considers the lobby, which functions as an arcade replete with shops, restaurants and other facilities - each of which is free-standing - as a separate structure.
The shape of the "nest" is one of a stylized saddle, i.e., it slopes gently downward toward the center from each end and from each side, but with a large center opening that can, however, be shielded from the elements by means of an enormous retractable roof. In addition, the top, or roof part, of the "nest" structure itself - as well as the retractable center roof, which is also of the same lattice construction as the "nest" - is closed ("rainproofed"), i.e., there are translucent, molded, inflated plastic pillows that cover the external side of the nest-like framework.
These molded, inflated plastic pillows are clad on their exterior surface with an environmentally safe coating of ETFE (Ethylene-tetrafluoroethylene - think Teflon®), while they are clad on their interior surface (their underside) with an acoustic membrane that absorbs sound in order to provide for the best possible acoustics for the stadium. Moreover, the upper part of the sides of the "nest" are covered with the same molded, inflated plastic pillows, except that, for aesthetic reasons, they are placed on the inner side of the nest-like framework.
Since all of the boutiques, restaurants, offices and other facilities within the Bird's Nest are self-contained, stand-alone buildings, the open-air, ventilated construction of the Bird's Nest does not present a problem during winter, while it provides cost-free circulation of air during the summer that reduces the need for air conditioning.
Enough sunlight (UV radiation) penetrates the roof, even when the center section is closed, to maintain the healthy growth of the grass on the ground below, without the use of artificial lighting for this purpose, while special gutters collect the rainwater runoff and lead it to a series of large containers in the cellar, where it is recycled. All in all, the Bird's Nest is a very well thought-out, environmental-friendly edifice that is at the same time timelessly beautiful to behold.
The "nest" draws its structural strength from its lattice construction, which forms a massive grid of seemingly intertwined (hence the building's suggestive title), crisscrossing, curved, rectangular steel "tubes" that are welded together, producing a very stable construction that can withstand gale force winds (note also that the retractable roof, or "lid", is made using a similar lattice construction).
The curved, rectangular steel "tubes" were produced in sections (each curved, rectangular "tube" (think of the shape of ventilation ducts in large buildings) is itself welded together, creating a hollow space inside it, therefore the term "tube"), then assembled (welded together) onsite, which made the erection of the Bird's Nest much simpler and much more managable. Due to this nest-like construction, with open, ventilated sides and with a "nest" roof made of translucent material, much sunlight penetrates the stadium, while the "twigs" of the "nest" cast a myriad of shadows, which some architectural art critics have likened to the pleasing, ambient experience of being in a sparsely populated forest that similarly allows in much diffuse sunlight.
The stadium covers an area of 258,000 square meters (308,565 square yards), is 68 meters (74 yards) high, is slighly oblong, measuring 333 meters (364 yards) from north to south and 298 meters (325 yards) from east to west, and will seat up to 80,000 spectators on a permanent basis, though, due to the demand for seats during the 2008 Olympic Games, the arrangers were permitted to make use of an additional 11,000 temporary seats, bringing the 2008 Olympic seating capacity up to a total of 91,000 seats. The seating stands are arranged in three concentric tiers.
The long-term plans for Beijing National Stadium is that it will continue to serve as the main venue for large-scale sports events, both on the national as well as on the international level, and as a venue for special cultural and entertainment (music, theatre, etc.) events that require a very large stadium with a very large seating capacity, and with the supporting infrastructure that a city such as Beijing can offer. In this connection, there are plans to construct a grand shopping mall and to build an international-class hotel adjacent to the stadium, in order to facilitate the continued use of the stadium for the above-mentioned sports, cultural and entertainment events.