When you see a sparkling, modern and beautiful glass building becoming a scenic spot in a big city, who invented the outer wall of the building? In 1976, the famous Chinese-American architect I. M. Pei put Mies'idea into reality and built the 60-storey Hancock Tower in Boston, USA, which is a skyscraper with glass exterior walls. This new building with transparent and mirror-like exterior walls is a great light in front of us. It immediately sensed the United States and the world. Glass exterior wall is called glass curtain wall, while Mies is known as "the father of glass curtain wall".
Nevertheless, the praise of Hancock Tower soon turned into criticism. The glass curtain wall of the building has used 10344 pieces of glass of 1.4 m x 3.5 M. Only three years ago, more than 2,000 pieces of glass were smashed. Beautiful tall buildings are full of holes. This is because the glass is not strong enough, and the steel frame supporting the glass is not strong enough. After five years of renovation, Hancock Mansion has managed to heal the "scars" on the outer wall. In recent decades, through continuous improvement, the quality of glass curtain wall has been significantly improved:
One is "steel". The impact strength of tempered (heat treated) glass is 3 to 5 times higher than that of ordinary glass, and even if it is broken, it will only break into small pieces without sharp angle. The new Huaqiang super-long LOW-E hollow glass is used in this picture of the Isbo Software Building.
The second is "hollow". Making curtain wall glass into double (or even three) layers and filling dry air or inert gas between two pieces of glass can greatly improve the performance of insulation, heat insulation and sound insulation. According to measurements, when the outdoor temperature is - 10 C, the temperature in front of the single-layer glass window is - 2 C, while the indoor temperature of the three-layer hollow glass is 13 C. It should be emphasized that the air filled with hollow glass must be dry, which is to prevent water vapor from condensing in the inner layer in winter, affecting transparency. This map is based on the new Huaqiang Shuangyin
The third is "double silver". Two very thin silver films are coated on the glass. This "double silver glass" can penetrate the visible light very well, but reflects the heat radiation (infrared) of the sun. In hot summer, double-layer silver hollow glass can shield 90% of the solar radiation heat through 90% of the visible light.