The article takes you to know more about glass curtain walls
About Glass Curtain Walls
The glass curtain wall in modern architecture adopts a combination of mirror glass and ordinary glass, and a hollow glass with dry air or inert gas filled in the interlayer. Hollow glass can be divided into two or three layers, with two layers of glass and a sealed frame forming a sandwich space; Three layers of glass constitute two interlayer spaces. Hollow glass has advantages such as sound insulation, heat insulation, frost resistance, moisture resistance, increased daylighting, and strong wind pressure resistance. However, there are also issues such as light pollution and high energy consumption.
(1) The glass curtain wall is a new type of contemporary wall. The biggest feature it gives to buildings is to organically unify factors such as architectural aesthetics, building functions, building energy saving, and building structure. It is light and beautiful, not easy to pollute, saves energy, etc. advantage. Choosing coated glass as the curtain wall can absorb infrared rays, reduce solar radiation entering the room, and lower the indoor temperature. It can not only reflect light like a mirror but also transmit light like glass. The inner side of the outer glass of the curtain wall is coated with colored metal coating. From the appearance, the entire exterior wall is like a mirror. Under the reflection of light, The room is not exposed to strong light and the vision is soft.
(2) Glass curtain walls also have some limitations, such as light pollution and high energy consumption. Coated glass or coated glass is used on the curtain wall of the building. When direct sunlight and skylight hit the glass surface, reflected glare is produced due to the specular reflection (i.e. regular reflection) of the glass. However, with the development of glass curtain wall technology and the continuous emergence of new material technologies, the materials used in glass curtain walls in buildings can now better solve the problems of light pollution and energy consumption.
Basic classification of glass curtain walls
1. Exposed frame glass curtain wall. An exposed frame glass curtain wall is a glass curtain wall with metal frame components exposed on the outer surface. It uses an aluminum alloy profile with a special cross-section as the frame, and the glass panel is fully embedded in the groove of the profile. Its characteristic is that the aluminum alloy profile itself has the dual functions of skeleton structure and fixed glass. Exposed frame glass curtain wall is the most traditional form, the most widely used, and has reliable working performance. Compared with hidden frame glass curtain walls, it is easier to meet the construction technical level requirements.
2. Hidden-frame glass curtain wall. The metal frame of the hidden-frame glass curtain wall is hidden on the back of the glass, and the metal frame cannot be seen outdoors. Hidden frame glass curtain walls can be divided into two types: fully hidden frame glass curtain walls and semi-hidden frame glass curtain walls. Semi-hidden frame glass curtain walls can be horizontally bright and vertically hidden, or vertically bright and horizontally hidden. The structural characteristics of the hidden frame glass curtain wall are: the glass is on the outside of the aluminum frame, and silicone structural sealant is used to bond the glass and the aluminum frame. The load of the curtain wall is mainly borne by the sealant.
3. Point glass curtain wall (metal support structure point glass curtain wall). A Point glass curtain wall is a glass curtain wall composed of glass panels, point support devices, and support structures. Point glass curtain wall has the stability of steel structure, the lightness of glass, and the precision of machinery. The glass of the point-type glass curtain wall is reliably fixed by using stainless steel claws to pass through the pre-drilled holes in the glass, while the general glass curtain wall is fixed to the frame with structural adhesive, and its surface glass is drilled at the corner. Finally, metal connectors are used to connect to the all-glass curtain wall of the supporting structure.
Generally, glass curtain walls are mostly flat frame structures with vertical rod stress systems. Compared with ordinary glass curtain walls, the point-type glass curtain wall's stress-bearing system is not in the frame, but in the support system. The glass panels on the point-type glass curtain wall are only connected to the supporting structure through a few points. There is almost no obstruction, the field of view is maximized, and the transparency of the glass is applied to the extreme. Therefore, white glass without light pollution is often used in the use of glass. , ultra-clear glass, and low-emissivity glass, especially the use of insulating glass, the energy-saving effect is more obvious.
Problems that are prone to occur in glass curtain walls
1. Glass curtain walls have poor fire resistance and are noncombustible materials. However, they can melt or soften in the face of intense fire, and glass breakage can occur in a short period of time. Therefore, in building design, the fire protection requirements of the building should be fully considered.
2. Structural adhesive failure: Due to long-term adverse factors of the natural environment, the structural adhesive is prone to aging and failure, resulting in the glass curtain wall falling. So in the design, it is advisable to use exposed or semi-concealed frame glass curtain walls as much as possible, because even if the structural adhesive fails, the support and constraints of the frame will greatly reduce the probability of glass falling.
3. Thermal stress causes the glass to break and expand when heated. If the heating is uneven, tensile stress will be generated inside the glass. When there are small cracks at the edges of the glass, these small defects are easily affected by thermal stress, ultimately leading to glass damage. Therefore, when installing glass, the edges of the glass should be finely processed to reduce the occurrence of cracks.
4. There are many reasons for water seepage in glass curtain walls, but the main reason is that the construction and sealing materials are closely related. Therefore, it is necessary to choose a construction party with strong technology and materials that meet national standards. To minimize water seepage to the greatest extent possible.