ATTEN: Manager Liu
ADD: Longhua Development Zone, Jing County, Hengshui City, Hebei Province
Landa Ville and Robert Ville in 1991, Green Buildings One by One Designed for Sustainable Morning. Developed countries are exploring the road of sustainable architecture, called "Green Building Challenge". That is, adopting new materials, new technologies, new design methods, new equipment and new technology, and implementing integrated design to minimize the resource and energy consumption of buildings in meeting their functions. Fuller, the greatest American architect and knot artist, puts forward the idea of "Doing the Most with the Least" structure (skeleton) saving material with the least structure, which is the most important content of green architecture and the glorious career that structural engineers pursue all their lives. However, the green building policy implemented by the Engineering Quality and Safety Supervision and Industry Development Department of the Ministry of Construction only talks about wall energy saving, not about steel skeleton material saving. In this way, many large steel nests, CCTV, Shenzhen Universiade Stadium, Hefei Innovation Hall and so on) are heavy and weird.
At present, the current situation of design and construction in our country is difficult to create. "Construction" also needs to design excellent steel structure, which is the excellent steel-bonded truss of green building. It must be steel skeleton material-saving, wall energy-saving, maximum satisfying function, minimum shadow environment, and provide healthy and comfortable activity space for people. It can also meet the concept of sustainable development in the whole life cycle of the building. In high-rise all-steel structures and long-span roof steel structures, steel structures have been widely used in advanced countries for more than 100 years (the number of steel structures in Japan has exceeded 70%) and can basically realize the three core values inherent in steel structures (Table 1). China has a long way to go in steel structure design. The top three high-rise steel structures in the world are all in the United States (Figure 3a). Among them, the box-shaped columns of the World Trade Center are only 450 mm x 450 mm, and the thickness is 7.5mm-12.5mm (Figure 3b); the distance between the columns below is increased, and there is no transfer floor; the high-rise three-storey buildings of silk-mounted parts are assembled with high-strength bolts, which are almost 100% of our existing buildings. Field welding and assembling make a sharp contrast.
The shear lag effect of this kind of outer frame tube (dense column + deep beam) joint is more serious. Sears Tower, built in 1974, adopted nine beam-framed tube structures, and the shear lag effect was significantly reduced. Although Sealstad is 26.213 m higher than the World Trade Center, the steel consumption is reduced by 26.5 kg/m2. Fig. 3a) The top three high-rise all-steel structures are all in the United States. Fig. 3b) World Trade Center draws a detailed picture of Georgia Dome, the world's most advanced large-span roof steel structure country, the main stadium of the 26th Olympic Games in 1996 (_4a), the elliptical plane 24079m * 192.02m, (roof + outer ring) steel consumption= (30 +) kg/m2. The world's first cable net structure is Raleigh Arena, USA. The largest span open-close steel latticed shell roof in the world is Fukuoka dome (Fig. 4c, D = 222m) with steel 30kg/m2 (Fig. 4b).
It consists of three fan-shaped revolving spherical reticulated shells, which can form three states: fully closed state, semi-open state (1/3 dome open state) and fully open state (2/3 dome open state). Because the roof is equipped with shock absorber and ingeniously constructed, the span-thickness ratio of fan-shaped spherical surface is 106.4/3.5=30.4. A Georgia Dome (1996) The world's most advanced cable-membrane dome (Cable membrane dome) B Raleigh Arena (1953, the world's first cable-net structure (30kg/m2 steel) 4C) Fukuoka dome (1993) -- the world's largest open-closed spherical reticulated shell structure (D = 222m) since the reform and opening up, China's steel structure building has developed rapidly. Because of the problem of design concept, many famous heavy and weird steel structures have been produced, which are compatible with green buildings. Academician Zu Yan severely criticized the following five steel structure projects (Fig. 5) in the theme report of "Affecting the Second Summit Forum of China's Steel Structure Industry", and pointed out rigorously that "the technological status quo emerging in recent years, which is contrary to the concept of light, fast, good and economical, is worrying.
Yao Bing, president of China Building Metal Structure Association, also pointed out in his speech at the Summit Forum: "The steel structure is not to say how big the volume is, or to say to use more steel, but to use steel rationally is to build the steel structure into a steel structure fortress."