Structural Design
Load Calculation
Wind Load: Determine the basic wind pressure value according to the meteorological data of the area where the building is located. Meanwhile, consider factors such as the building’s height, shape coefficient, and wind vibration coefficient to accurately calculate the wind load borne by the curtain wall. For example, for super – high – rise buildings, the value of the wind vibration coefficient needs to be determined through specialized wind tunnel tests to ensure the safety of the curtain wall under strong wind.
Earthquake Load: Calculate the seismic action effect according to the seismic fortification intensity and site category of the area where the building is located, in accordance with relevant codes. For areas with high – intensity fortification, special attention should be paid to the seismic design of the curtain wall, and connection structures that can effectively absorb and dissipate seismic energy should be adopted.
Self – weight Load: Accurately calculate the self – weight of the curtain wall, including the weights of all components such as the panel, framework, and connectors. For large – scale stone curtain walls or heavy – metal curtain walls, the self – weight load may have a significant impact on the structure, and a reasonable support structure needs to be designed to bear the load.
Curtain Wall System Selection
Framed Curtain Wall: It is suitable for various scales and types of buildings. Its advantages include flexible installation, which can be adjusted according to the on – site construction conditions, and convenient maintenance and replacement. During the design, the spacing of the columns and beams should be reasonably arranged. Generally, the column spacing should not be too large to ensure the overall stiffness of the curtain wall.
Unitized Curtain Wall: It has high integrity and waterproof performance, which can effectively improve the construction efficiency. It usually consists of independent unit panels that are assembled in the factory and then transported to the site for installation. During the design, the connection method and sealing performance between the unit panels should be the key considerations to ensure the stability of the entire curtain wall system.
Component Design
Column Design: According to the height, span, and load conditions of the curtain wall, select the appropriate cross – section form of the column, such as rectangular, circular, or special – shaped cross – sections. Increasing the wall thickness of the column can improve its bearing capacity and flexural stiffness. At the same time, the connection points of the column should be reasonably set, and reliable connection methods such as bolt connection or welding should be adopted to ensure the firm connection between the column and the main structure.
Beam Design: The main function of the beam is to support the panel and transfer the load to the column. During the design, the spacing and cross – section size of the beam should be determined according to the size and weight of the panel. Generally, the spacing of the beams should be determined according to the material and specification of the panel to ensure that the panel will not produce excessive deformation when subjected to the load.
Reinforcement Rib Design: For large – size panels or curtain wall components that bear large loads, setting reinforcement ribs can effectively improve their stiffness and strength. The layout and size of the reinforcement ribs should be optimized according to the stress conditions of the components. For example, in the aluminum – plate curtain wall, strip – shaped or grid – shaped reinforcement ribs can be set on the back of the aluminum plate.
Material Selection
Panel Material
Glass Panel: Tempered glass is preferred. Its strength is much higher than that of ordinary glass, and after breaking, it forms small particles, which is not easy to cause injury, ensuring good safety. For high – rise curtain walls or places with special requirements, laminated glass can be used, that is, a layer or multiple layers of PVB film are sandwiched between two or more layers of glass. Even if the glass breaks, the fragments will be adhered by the film and will not fall off.
Metal Panel: Aluminum plate is a commonly used metal panel material, which has the advantages of light weight, strong corrosion resistance, and easy processing and molding. To improve the strength and durability of the aluminum plate, its surface can be treated, such as fluorocarbon spraying or anodizing. Stainless – steel plate can also be used for curtain walls. It has high strength and good corrosion resistance, but the cost is relatively high.
Stone Panel: Natural stone with hard texture and high strength, such as granite, should be selected. At the same time, the stone should be tested for radioactivity and physical properties to ensure that it meets the relevant standard requirements. To prevent problems such as cracking of the stone during use, the stone can be reinforced with back – ribs.
Framework Material
Aluminum – alloy Profile: It has the characteristics of light weight, good corrosion resistance, and excellent processing performance. When selecting aluminum – alloy profiles, the appropriate alloy grade and heat – treatment status should be chosen according to the load requirements and use environment of the curtain wall. For example, 6061 – T6 aluminum alloy has high strength and hardness and is suitable for curtain wall structures that bear large loads.
Steel: For some curtain walls with high – strength requirements, such as large – span or high – rise curtain walls, steel can be used as the framework material. Commonly used steels include Q235 and Q345, etc. During the design, the rust – prevention problem of steel should be considered, and effective anti – corrosion treatments such as spraying anti – rust paint or using the hot – dip galvanizing process should be carried out.
Connection Material
Bolt: High – strength stainless – steel bolts should be selected to ensure the reliability and durability of the connection. The diameter, length, and tightening torque of the bolts should be calculated and determined according to the stress conditions of the connection parts to avoid problems such as bolt loosening or fracture.
Sealant: Silicone sealant is a commonly used sealing material in curtain walls, which has good weather resistance, water resistance, and bonding performance. When selecting the sealant, the appropriate type and specification should be chosen according to the use environment and sealing requirements of the curtain wall to ensure a good bonding effect between the sealant and the curtain – wall materials.
Connection and Structural Design
Connection between Column and Main Structure: A reliable connection method should be adopted. The column is connected to the main structure through pre – embedded parts or post – embedded parts. The pre – embedded parts should be accurately embedded during the construction of the main structure to ensure that their positions and accuracies meet the design requirements. The post – embedded parts need to be drilled on the main structure and fixed with chemical anchor bolts or expansion bolts. During the construction, the drilling depth and diameter should be strictly controlled to ensure the anchoring force of the anchor bolts. A special connection method is adopted to make the column and the main body firmly connected and safer. During the design and construction, the design distance of the wall should be paid attention to, because safe construction is required. If it is too close, it is very easy to have safety problems.