Guangdong Weguard Construction Technology Co., Ltd.
Address: Baishe Xiashe Industrial Zone, Hongxing Village, Guanyao, Shishan Town, Nanhai District, Foshan City, Guangdong Province
In the new building that has been completed for three years, 115 glass curtain walls have exploded. In the special inspection activities of the CPPCC “Safety Situation of High-rise Buildings and Glass Curtain Walls in the City” held yesterday, this year’s frequent high-altitude “glass rain” accidents caused strong concern from the members. The Municipal Construction and Communications Commission revealed that it is proposed to establish a curtain wall construction management information system covering from design and construction to use and maintenance management to establish a complete information “ID card” for each glass curtain wall building in Shencheng.
The new building exploded 115 glass walls in 3 years
"Take the naked eye every two hours. Can such a patrol really find the problem glass curtain wall?" A famous commercial building in Lujiazui had a glass curtain wall blasting incident twice this year. Yesterday, the members of the CPPCC special inspection team took the lead in this "defect". However, Zhang Lijun, the vice chairman of the Standing Committee of the CPPCC and the municipal party committee of the Zhi Gong Dang, did not buy the rectification measures taken after the accident.
At noon on May 18 this year, the building suddenly burst into a "glass rain." It turned out that a tempered glass curtain wall with an area of about 4 square meters on the 46th floor suddenly burst. Fortunately, the accident did not cause casualties. However, the parking lot adjacent to the building failed to escape. The nearly 50 cars parked inside were damaged to varying degrees, and the most serious whole windshield was smashed. Two months later, the outer glass of a glass curtain wall on the 43rd floor of the building was also broken. Fortunately, it was not left yet and no one was injured.
Building Development Company and Shanghai Diweixing Real Estate Development Co., Ltd. said at the forum that the current building glass area is currently 38,000 square meters, with a total of 24,000 pieces. Among them, two-layer hollow low-reflection glass reached 21,812 pieces, and single-piece glass was 1948 pieces. Since the completion of the building in the past three years, a total of 115 pieces of glass have been self-exploited, and the self-explosion rate has reached 4.79‰, which is lower than the self-explosive average of 5.5‰ in the domestic industry.
“The company tested the self-explosive glass after the incident. According to the test results, the stiffness and hardness of the glass are in line with national standards. Because there is impurities in the tempered glass, it will cause self-explosion after being heated.” Chairman of Shanghai Diweixing Real Estate Development Co., Ltd. Jun Ping said, "At present, the company has increased the frequency of inspections on the building, sending people to inspect the naked eye every 2 hours, and discovering the problem glass curtain wall."
The self-detonation rate of a building is four thousandths. What about the glass curtain wall of so many high-rise buildings in Shanghai? Such rectification measures made Zhang Lijun very uneasy: "In the face of the glass curtain wall covered with the entire building, can a two-hour visual inspection really reveal a safety hazard?"
20 years old, some glass curtain walls are old
Since the earliest use of the glass curtain wall in the Friendship Building in 1984, up to now, there have been 20,579 high-rise buildings (more than 8 floors), of which 980 have more than 30 floors (over 100 meters for super high-rise buildings); glass curtain wall buildings have been built. 2633 buildings, including more than 1,500 high-rise curtain wall buildings. About 80% of high-rise buildings were built in the past ten years after 2000, mainly located in Pudong, Minhang, Xuhui, Putuo, Baoshan and other districts, of which more than 30 layers are concentrated in Xuhui, Pudong, Putuo, Changning and other districts.
Shen Xiaosu, deputy director of the Municipal Construction and Communications Commission, said that after more than 20 years of construction, a considerable part of the city's already built high-rise and curtain wall buildings are old, especially glass curtain wall high-rise buildings, glass bursts, hardware construction corrosion, deformation, weathering aging, turtles Cracks, stress builds and other problems, under the influence of typhoon or gravity, there are security risks.
"In May this year, there were three accidents involving glass curtain wall and door and window glass fall. According to the investigation, some reasons are because the sash window frame is closed and not sealed, and some are caused by external force to cause the glass to rupture, and some because the glass blew." Shen Xiaosu said.
In 1996 and 1998, the Municipal Construction and Transportation Committee made clear regulations on the materials, spare parts and installation of the glass curtain wall. Since 2005, in accordance with the national requirements for building energy conservation and strengthening the safety of glass curtain walls, the "Shanghai version requirements", which must use double-layer hollow safety glass, have been made.
In 2006, the Municipal Construction and Communications Commission and the Municipal Housing and Lands Bureau jointly launched a special investigation on glass curtain wall construction, and took measures against the “problem building”. In July this year, the Municipal Construction and Communications Commission will once again open with the Municipal Housing Management Bureau to carry out special inspection and rectification work. The main contents include: opening the safety and quality of doors and windows, structural rubber (sealing adhesive) and seal strip safety and quality, glass safety and quality, and stress. The safety quality of components and the leakage of rainwater affect safety and quality. The entire special inspection and rectification work is scheduled to end at the end of March next year.
Glass curtain wall must have special maintenance funds
How to dynamically monitor these potential security risks? Shen Xiaosu revealed that the city will build a glass curtain wall building database. Combined with the special rectification data of the glass curtain wall in 2006 and the special approval data of the curtain wall over the years, the city decoration and decoration association will carry out data entry. There are currently 2,633 data entered. At the same time, it is planned to establish a classification database of glass curtain wall buildings from aspects of planning, design, construction, testing, completion acceptance, and safety maintenance. Establish a complete information “ID card” for each glass curtain wall building, and fully grasp the design, construction, use and maintenance of the curtain wall building.
The Municipal Construction and Communication Commission and relevant departments have studied and drafted relevant management measures. Shen Xiaosu revealed that in the early stage of the construction of the glass curtain wall, the provisions should include: when planning, emphasize the control of the total amount; before the project is established, inform the relevant regulatory requirements of the glass curtain wall in advance. Even if approved, it should not exceed 70% of the total wall area. Glass curtain walls will be banned in hospitals, nursing homes, schools and kindergartens. For certain areas with sensitive targets, consideration will not be given to the construction of glass curtain wall construction, after the city has “rejected” more than 20 applications for such glass curtain wall construction.
In the construction phase, the design, construction, and maintenance units must be integrated. The entire construction must have special construction plans, supervision reports, completion acceptance, etc., and the warranty period for the glass curtain wall must be 5 years.
In the safe use phase, it is proposed to reserve special maintenance funds in advance of the construction of the glass curtain wall; and the professional units will carry out daily maintenance and regular inspections. If the service life is exceeded, the curtain wall should be evaluated for safety. Once problems are found, repairs should be rectified in a timely manner. If it cannot be repaired in time, a safety warning must be set up.
Give each glass curtain wall an "ID card"
Tu Haiming, member of the CPPCC National Committee, vice chairman of the Overseas Chinese Federation, and chairman of Shanghai Haodu Real Estate Development Co., Ltd. said that there are many new situations, new problems and new hidden dangers in the glass curtain wall of the high-rise buildings in this city.
Why are so many developers keen on the "glass curtain wall"? Because Shanghai's geology is a soft soil structure, a building has a construction area of tens of thousands to hundreds of thousands of square meters, and the weight of the glass curtain wall is only one-twelfth of the brickwork, which is equivalent to one tenth of the concrete wall. In addition, the installation is simple, the price is low, the progress of the project is fast, and the building volume ratio can be improved. It has a great advantage in construction and becomes the "darling" of the developer.
Why is the glass curtain wall in Shanghai so "cannot stand the test"? Generally, there are three reasons for the self-exposure of tempered glass in glass curtain wall: one is external force extrusion, the other is that the temperature difference is too large, and the third is that the glass material has a volume expansion of impurities called nickel sulfide.
"At present, the glass blasting probability of glass curtain walls in overseas cities such as New York, Tokyo, Hong Kong, Singapore, etc. is one in ten thousand, and the probability of glass curtain wall cracking in large cities such as Beijing, Shanghai, Guangzhou, Shenzhen is also a thousand points. Third, but Shanghai should push the glass bursting probability of the glass curtain wall to a lower level and press it to the lowest level." Tu Haiming said.
The barriers to entry, design, production, installation and maintenance of Shanghai in this field are too low. There are more than 100 manufacturers of large-scale tempered glass curtain wall produced in Shanghai, which is completely different. In addition, the city's inspection and evaluation institutions for glass curtain walls are rare, and professional maintenance companies are rare.
For the glass curtain wall, in Hong Kong, China, there is a strict access system for this industry, whether it is design, installation, supervision, maintenance, maintenance, all licensed operations, certification, and third-party mandatory testing; The use of glass curtain walls has been clearly restricted, and light aluminum alloy materials have been used. In Japan, it has been stipulated that the use of glass curtain walls in buildings on the side of the pedestrian street in downtown areas and non-street areas must use not broken glass. .
Zheng Long, the Standing Committee of the CPPCC and the Director of the Electricity Commission of the Municipal Economic and Information Commission, also added that in places where conditions permit, green belts can be built as isolation to avoid "glass rain" injury.
Tu Haiming finally suggested: It is necessary to strictly control the number of glass curtain walls for new high-rise buildings; quickly formulate mandatory regulations for the use, installation and maintenance of glass curtain walls; establish and improve the qualification review and access system for glass curtain wall production, construction, installation and maintenance enterprises; Establish a variety of information files for the city's glass curtain wall, and introduce an international standard system for the construction and maintenance of high-coefficient, safe glass curtain walls.