Detailed explanation of the advantages, disadvantages, and technical details of glass curtain walls

1、 Overview of Glass Curtain Wall

The glass curtain wall widely used in modern architecture is mainly based on the combination of mirror glass and ordinary glass, and is designed with insulated glass filled with dry air or inert gas in the partition. This type of insulated glass can be divided into two types: two-layer and three-layer. The two-layer insulated glass is combined with a sealed frame to form a closed interlayer space; And the three-layer glass cleverly constructs two sandwich spaces. Hollow glass not only has excellent sound and heat insulation properties, but also effectively prevents frost and moisture from entering, while increasing the building's lighting and enhancing its wind pressure resistance. However, glass curtain walls also have certain shortcomings, such as potential light pollution and high energy consumption.

1. Discussion on advantages and disadvantages

(1) Highlights of glass curtain wall

As an innovative wall design in modern architecture, glass curtain walls cleverly integrate architectural aesthetics, practical functions, energy-saving effects, and structural stability. This design allows buildings to exhibit ever-changing color tones under different angles and lighting conditions, providing people with a dynamic aesthetic experience.

(1) Highlights of glass curtain wall

Glass curtain walls occupy a place in modern architecture with their unique charm. The reflective insulating glass used has a thickness of only 6 millimeters and a wall weight of about 50kg/㎡. It is both lightweight and beautiful, and has many advantages such as low pollution and energy conservation. This type of glass is made by adding trace metal elements and tempering it on the basis of float glass, forming a transparent and hard plate-like glass. It can effectively absorb infrared radiation, thereby reducing the amount of solar radiation entering the room and lowering the indoor temperature. In addition, this type of glass also has dual functions of reflection and transmission. The inner side of the outer glass of the curtain wall is coated with colored metal coating, making the entire exterior wall look like a huge mirror. Under the illumination of light, it not only reflects brilliant radiance, but also ensures soft indoor lighting, resulting in excellent visual effects.

(2) Shortcomings of Glass Curtain Walls

Although glass curtain walls have many advantages, their shortcomings must also be acknowledged. One of them is the problem of light pollution. Due to the extensive use of coated glass or coated glass on building curtain walls, these glasses will produce specular reflection, also known as normal reflection, under direct sunlight and sky light, thus forming reflected glare, which has a certain impact on the surrounding environment and residents' lives. In addition, the energy consumption issue of glass curtain walls is also worth paying attention to. Due to the good transparency of glass, a large amount of solar radiation enters the room during summer, increasing the load on air conditioning and causing energy waste.

However, with the continuous advancement of glass curtain wall technology and the continuous innovation of new material technology, the glass curtain wall materials currently used in buildings can effectively address light pollution and energy consumption issues.

2、 Basic classification of glass curtain walls

Glass curtain walls, as an important component of modern architecture, have various classification methods. According to different standards, we can classify it into multiple types. These types not only differ in performance, but also have their own strengths in application scenarios and design styles. Understanding these classifications helps us to gain a deeper understanding of the evolution and development of glass curtain wall technology.

1. Clear frame glass curtain wall

The metal frame components of the clear frame glass curtain wall are clearly visible. This curtain wall is mainly made of aluminum alloy profiles with special cross-sections, and the glass panels are completely embedded in the grooves of the profiles. This design allows the aluminum alloy profile to serve as both a supporting framework and a fixed glass. Clear frame glass curtain wall is the oldest form of curtain wall in history, widely used and with stable performance. Compared to hidden frame glass curtain walls, the construction process requirements are more direct and clear.

2. Hidden frame glass curtain wall

The design of the hidden frame glass curtain wall is ingenious, with its metal frame completely hidden behind the glass, making it impossible to see its trace from the outside. There are also two types of curtain wall forms: fully hidden frame glass curtain wall and semi hidden frame glass curtain wall, which can be further divided into two layouts: horizontal and vertical hidden and vertical and horizontal hidden. In terms of construction, the characteristic of the hidden frame glass curtain wall is that the glass is located on the outside of the aluminum frame, and the glass is tightly bonded to the aluminum frame through silicone structural sealant, thereby forming a stable curtain wall structure. It is worth noting that the load of this curtain wall mainly relies on sealant to bear, ensuring its stability and safety.

3. Point type glass curtain wall

Point type glass curtain wall is a curtain wall system composed of glass panels, point support devices, and support structures, which combines the stability of steel structure, the lightness of glass, and the precision of machinery. Its uniqueness lies in the reliable fixation of glass through pre drilled holes through stainless steel claws, rather than traditional structural adhesive bonding. This design allows the face glass to be connected to the supporting structure through metal connectors after drilling holes at the corners, thus forming a different force system from general glass curtain walls. The support system of point type glass curtain wall bears the main load rather than the frame. The glass panel is only connected to the support structure through a few points, with almost no obstruction and extremely high transparency. White glass, ultra white glass, and low radiation glass that do not cause light pollution are often used, especially in the application of insulating glass, where energy-saving effects are more significant. However, it should be noted that this type of curtain wall does not have an opening fan design.

3、 Technical points

The technical requirements for point glass curtain walls cover multiple aspects. Firstly, its design needs to fully consider the principles of mechanics to ensure stability. The connection between the glass panel and the supporting structure is unique, and reliable fixation is achieved by passing stainless steel claws through pre drilled holes, thereby forming an efficient force system. In addition, the selection of materials is also crucial, usually using non light polluting white glass, ultra white glass, and low radiation glass to ensure transparency while achieving energy-saving effects. During the construction process, it is necessary to strictly control the quality of each link to ensure the safety and durability of the point glass curtain wall.

1. Selection and Application of Sealing Materials

In the construction of point glass curtain walls, the gaps between glass should be sealed with weather resistant silicone adhesive to ensure good weather resistance. At the same time, structural silicone adhesive is used for the connection between glass and metal structures to achieve a strong bond. It is worth noting that in architectural point glass technology, sealant mainly plays a sealing role and does not require strength calculation. However, strict compatibility testing and performance testing must be conducted before use to ensure that the selected sealant matches the contact material and is used within its validity period. In addition, operating procedures should be strictly followed during the construction process to ensure construction quality.

2. Selection of Glass

In the construction of glass curtain walls, priority should be given to using curtain wall glass with a reflectivity not exceeding 0.30 to ensure good transparency. For glass curtain walls that require lighting, the lighting reduction factor should not be less than 0.20 to meet the lighting needs. In the context of frame supported glass curtain walls, it is recommended to use safety glass, such as laminated glass, tempered glass, or laminated glass, to ensure safety during use. For the panel glass of point supported glass curtain walls, tempered glass should be specifically selected to ensure its structural stability.

3. Selection and Processing of Metal Materials

Steel, as a type of metallic material, must undergo anti-corrosion treatment on its surface to ensure its durability. If hot-dip galvanizing is used for corrosion prevention, the thickness of the galvanized film should be at least 45 μ m; If electrostatic spraying is chosen, the film thickness should not be less than 40 μ m. In addition, to prevent possible electrochemical corrosion between different metal materials, it is necessary to ensure good insulation measures between each metal material.

4、 Common problems with glass curtain walls

Glass curtain wall, as a common design element in modern architecture, although beautiful and elegant, there are also many problems in its use. These issues not only affect the service life of curtain walls, but may also pose a threat to the safety and stability of buildings. Therefore, maintenance and repair work for glass curtain walls is particularly important.

1. Insufficient fire resistance performance

Although glass curtain walls themselves are not combustible materials, they may soften or melt under the action of high temperatures and flames, and even cause glass breakage. This situation must be fully considered in architectural design to ensure that the building meets the corresponding fire safety standards.

2. Structural adhesive failure

Due to long-term exposure to natural environments, glass curtain walls may face various adverse factors, leading to the gradual aging and failure of structural adhesives, thereby causing the risk of glass curtain wall falling. To address this issue, in architectural design, priority should be given to using visible or semi hidden frame glass curtain walls. In this way, even if the structural adhesive fails, the stability of the frame can effectively reduce the possibility of glass falling.

3. Glass fracture caused by thermal stress

Glass will expand when heated, and if heated unevenly, it will generate tensile stress inside. When there are small cracks at the edge of the glass, these cracks will gradually propagate due to thermal stress, ultimately leading to glass fracture. Therefore, during the installation of glass, it is necessary to finely process the edges of the glass to reduce the possibility of cracking.

4. Water seepage problem

The water seepage of glass curtain walls may be caused by various factors, among which the selection of construction quality and sealing materials is particularly crucial. To reduce water seepage, a skilled construction team should be selected and high-quality materials that meet national standards should be used.