With the rapid development of China's national economy and the continuous improvement of people's living standards, as well as the enhancement of architects' design concept of "Humanity in architecture", buildings are increasingly developing towards high-rise, high-end and multi-functional directions. Therefore, building curtain wall products are bound to develop in the direction of high technology and multi-functionality in order to adapt to people's increasingly enhanced awareness of environmental protection and energy conservation and meet the market's demand for the functions of building curtain walls.
Double-layer curtain walls or ventilated curtain walls, as a relatively popular building envelope structure, originated in North America and have been widely applied in Europe. In terms of ventilation methods, it can be divided into two major systems: internal ventilation and external ventilation. The outer layer of the double-layer curtain wall with internal ventilation is a closed structure. The air exchange takes place in the two layers of the curtain wall space. Usually, it requires the cooperation of a centralized forced ventilation system to exchange with nature and achieve the final effect. The double-layer curtain wall system with internal ventilation is widely used in Italy. External ventilation takes advantage of the air outside the building. Through the reasonable organization of air flow at the air inlets and outlets of the double-layer curtain wall, it directly exchanges with nature to achieve the final effect. The external ventilation double-layer curtain wall is widely used in Germany and the United Kingdom.
The ventilation height of the curtain wall may be the height of a single layer, multiple layers or even the entire building, or some combination of the above situations. The most common type is the single-layer height structure. The advantages of single-layer and double-layer curtain walls are: there is separate fire, smoke, odor and noise between floors, and it is easy to achieve standardized design and production of curtain wall units.
In temperate climates such as continental Europe and the United Kingdom, double-layer curtain walls are widely used in the construction industry. Experts in the construction field believe that double-layer curtain walls can reduce the cooling load, facilitate good natural ventilation, improve lighting, control noise, and lower heat energy consumption, etc.
Generally speaking, the cost of double-layer curtain walls is much higher than that of ordinary curtain walls. Therefore, it is necessary to explore new curtain wall structures that not only have the superiority of double-layer curtain walls but also the economy of ordinary curtain walls.
This article introduces a kind of building curtain wall structure that has been applied abroad for the reference of curtain wall designers.
2. The structure of the economical double-layer ventilation curtain wall
The economic double-layer ventilation curtain wall adopts the structural form of an integral unit system. The spacing between the inner and outer curtain wall panels is 155mm. The entire system structure is light, simple and economical. The curtain wall frame is made of aluminum alloy keel, which is processed, fabricated and assembled in the factory. The surface materials adopt insulating glass, single-layer glass and inner insulation decorative panels. The waterproof and sealing rubber strips (pads) are made of ethylene propylene diene monomer (EPDM) or silicone, and the hardware accessories in contact with aluminum alloy are made of stainless steel. Then it is transported to the site and directly hung on the main structure of the building.
Science Popularization China · Science Encyclopedia Glass Curtain Wall
A glass curtain wall refers to a building's exterior envelope or decorative structure composed of a supporting structure system and glass, which can have a certain displacement capacity relative to the main structure and does not share the forces acting on the main structure. Walls with single and double layers of glass. The reflective insulating glass is 6 millimeters thick, and the self-weight of the wall is approximately 40 kilograms per square meter. It has the advantages of being lightweight, aesthetically pleasing, not prone to pollution, and energy-saving. The inner side of the outer glass of the curtain wall is coated with a colored metal film. From the outside, the entire exterior wall looks like a mirror, reflecting the sky and the surrounding environment. When the light changes, the image is colorful and ever-changing. Under the reflection of light, the interior is not exposed to strong light, and the visual effect is soft. It was first adopted in the Great Wall Hotel project in Beijing in China in 1983.
Those who have visited New York, USA, are generally impressed by its bustling urban landscape. The skyscrapers that reach into the clouds are spectacular, and their all-glass curtain walls reflect the clear blue sky and dancing white clouds, adding even more brilliant colors to it. So, how is a glass curtain wall made? Glass curtain wall refers to the mirror-like glass used as the exterior decoration of buildings. It is made by adding trace amounts of Fe, Ni, Co, Se, etc. to the composition of float glass and then tempering it into a colored transparent plate glass. It can absorb infrared rays, reduce the solar radiation entering the room and lower the indoor temperature. It can both reflect light like a mirror and allow light to pass through like glass.
The glass curtain walls of modern high-rise buildings also adopt insulating glass composed of mirror glass and ordinary glass, with dry air filled in the interlayer. Insulating glass can be divided into two-layer and three-layer types. Two-layer insulating glass is composed of two layers of glass and a sealed frame, forming an interlayer space. Three-layer glass is composed of two interlayer Spaces formed by three layers of glass. Insulating glass has the advantages of sound insulation, heat insulation, anti-frosting, moisture-proofing and high wind pressure resistance. According to measurements, when the outdoor temperature is -10℃, the temperature in front of a single-pane glass window is -2℃, while the indoor temperature using triple-pane insulating glass is 13℃. In summer, double-layer insulating glass can block 90% of the solar radiation heat. Sunlight can still penetrate the glass curtain wall, but it won't make one feel hot when exposed to it. Rooms with insulating glass curtain walls can be warm in winter and cool in summer, greatly improving the living environment. The middle is made of PC sunlight glass -PC board, which can withstand high temperatures up to 135 degrees and low temperatures down to -45 degrees.
