Technical Exchange of Registered Architects: Analysis of Problems in Engineering Glass Curtain Wall
Fanyu
Www.glass.com.cn
2018-04-03 11:26:36
| TheGlass blast caused by nickel sulfide The There are many reasons for causing glass breakage. The following analysis and demonstration will be made on the broken glass caused by nickel sulfide and thermal stress. The Nickel sulphide is an unavoidable harmful impurity in the glass production process. Nickel sulphide itself does not cause any damage to the glass. However, when the curtain wall glass containing nickel sulphide is installed in the curtain wall, the volume of the nickel sulphide is slightly increased due to the increase of the external temperature. The change causes tiny cracks inside the glass. These cracks penetrate the tension layer of the tempered glass and release the internal energy, causing the glass to break.  The solution is to start from the source and the glass manufacturer should monitor the glass manufacturing process to minimize the contact between the nickel-containing material and the glass raw material. Secondly, after monitoring the installation of curtain wall glass, foreign countries have used photographic methods to detect the presence of nickel sulphide impurities. If it is contained, necessary replacements must be made in time to prevent injury after the glass is broken. It is also possible to replace monolithic tempered glass and tempered hollow glass with laminated glass. If the nickel sulfide impurity breaks down the glass due to deformation, the fragments will still adhere to the film so as not to cause glass rain and damage the ground personnel. The TheGlass breakage caused by thermal stress The Thermal stress is an important cause of the crushing of glass curtain walls. There are many reasons for the heat of the glass curtain wall, but the main source of heat is sunlight. When the sun shines on the surface of the glass curtain wall, the glass will be thermally expanded. If the glass is heated evenly, the edge of the glass and the central part of the glass will expand at the same time, but if the edge Non-uniform internal heating of glass and glass will generate tensile stress inside the glass. When there are cracks or micro cracks on the edge of the glass, these crucibles are easily affected by thermal stress. With the increase of temperature difference, thermal stress causes cracks to gradually increase. Big causes broken glass. The The solution is to first finish the edge of the glass and use fine-edged or polished edges to reduce the presence of micro cracks; second is to temper the glass to enhance the glass's ability to resist temperature changes; the third is in glass. During processing, handling and installation, the glass must be properly protected. Be careful not to collide or rub the edges of the glass with other hard objects. Observe the operating procedures strictly, especially during the installation if the frame is not suitable (too small or distorted Deformation), we must remember not to clamp off the glass corners with pliers, be sure to correct the frame to adapt to the size of the glass. The TheGlass curtain wall has poor fire protection The The glass curtain wall is an incombustible material, but it can be softened or even melted in the face of a fiery fire. Therefore, in building design, we must fully consider the building's fire protection requirements. The fireproof effect, fire-resistance integrity, and fire-resisting and heat-insulating property of general glass curtain walls are very low, and glass breakage will occur in a fiery fire in a short time. The The solution is that during the actual construction process, the designer will carry out different designs according to the different fire protection requirements of the building. For buildings with general fire protection requirements, glass is made of glass bricks,Tempered glassSmall flat glass, etc. For buildings with higher fire protection requirements, curtain wall glass uses wire-bonded glass, single-piece fire-resistant glass, composite fire-resistant glass, and fire-resistant insulating glass. The composite fireproof glass is a fireproof curtain wall glass that is widely used at present. When a fire occurs, the glass on the fire surface is burst by heat during a certain period of time. However, due to the presence of a fireproof film, the glass is adhered to the film and does not fall and the integrity of the glass is maintained. Sex. At the same time, since the film itself has a fire-retardant effect, it not only blocks the propagation of fire, but also ensures that the temperature of the back-fire surface does not rise rapidly, and controls the spread of fire. The TheCurtain wall glass structural adhesive failure The Glass curtain walls have long been affected by the unfavorable factors of the natural environment, such as wind, sun, rain, ultraviolet rays, earthquakes, etc. Therefore, the glass curtain walls must have weather resistance, durability, and corrosion resistance as bonding materials. Structural adhesives have become the focus of attention. In Beijing, Shanghai, Guangzhou, and other cities where glass curtain walls were used early, curtain wall glass falls often occur. How to measure the failure of a piece of glass structural adhesive can be said to be more difficult, but to ensure the safety of people and vehicles, if The large-scale replacement of glass curtain walls is a huge expenditure. In the face of this situation, the owners are in a dilemma.The The solution is to firstly restrict the use of hidden glass curtain walls, and must protect the glass curtain walls that have passed the quality assurance period, such as setting up fences, green belts, hanging curtains to prevent falling glass and pedestrians passing by and around the glass curtain wall. vehicle. The second is to use the glass frame of the open frame and the semi-hidden frame as much as possible, because even if the structural adhesive fails, due to the support and constraint of the frame, the probability of dropping the glass will be greatly reduced. The The Glass curtain wall support structure failureThe Not all problems with glass curtain walls are caused by the glass itself. Sometimes the failure of the frame structure supporting the glass will cause problems with the glass curtain wall. The frame structure used to support the glass is often the weak link of the glass curtain wall. If the design of the initial frame system is unreasonable, the frame structure cannot withstand the gravity in the building, and then it will deform and eventually lead to glass breakage. The The solution is to carry out anti-fatigue experiments on the frame structure during the design process, and then design the corresponding curtain wall glass according to its anti-fatigue capability to prevent the frame from being overloaded for a long time. The The Failure of glass curtain fastenersThe All glass curtain walls rely on fasteners to unite the curtain wall and fix it on the building. However, unpredictable defects in the fastener fixing device may cause serious structural problems and even cause the glass of the curtain wall to fall. The The solution is to perform the necessary inspections on fasteners before installing the glass curtain wall, and install and use them on-site after passing the inspection. In addition, for the curtain wall glass fall caused by the loosening of the fixed bolts, during the actual construction process, special locking nuts are used to lock the bolts to prevent the bolts from slipping and failing, or a specific washer is used to ensure that the bolts do not fall off after being fastened. The The Other problems caused by glass curtain wallThe The above problems caused by the glass curtain wall are due to the large-area use of glass curtain walls. Light pollution, color pollution, and thermal pollution are some problems that cannot be ignored. Although glass curtain walls have such problems, but as designers, producers, users as long as they fully understand and avoid weaknesses, then the glass curtain wall is still a highlight of modern architecture. |