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Lightning protection of high-rise buildings should be repaired both inside and outside

In recent years, high-rise buildings have been struck by lightning repeatedly. Is the higher the building, the greater the risk of lightning stroke? How should high-rise buildings be protected against lightning? With these questions, the reporter interviewed Guan Xiangshi, a famous lightning protection expert in China and a Chinese expert of IEC / tc81 / WG3 Lightning Protection Committee of the International Electrotechnical Commission.
The higher the building, the greater the risk of lightning stroke
Guan Xiangshi said that it is normal for high-rise buildings to be struck by lightning. The higher the building, the closer it is to the thunder cloud, and the greater the risk of being struck by lightning.
Built in 2004, it was not officially opened until 2010. It is the tallest building in the world and has been struck by lightning for many times. It is understood that lightning 3 to 5 kilometers away from the ground can produce an average voltage of more than 100 million volts. However, the spire of the tower is made of 4000 tons of steel and acts as a lightning rod to protect the whole building from lightning. Therefore, despite several lightning attacks, the Khalifa tower is still safe and sound.
The first TV tower struck by lightning in the world is the Ostankino radio and television tower in Moscow, known as “the first tower in Europe”. The radio and television tower is 573.5 meters high and has been struck 143 times in four and a half years. In China, in April 2010, the small ball on the top of the Oriental Pearl Tower in Shanghai was struck by lightning. What is the lightning strike in the Oriental Pearl Tower in Shanghai? Why can’t we stop the lightning strike? “In fact, lightning protection can only intercept lightning.” Guan Xiangshi said, “the correct name of lightning rod should be ‘lightning arrester’. As the name suggests, lightning arrester is to intercept lightning.”
Guan Xiangshi said that from the perspective of building lightning protection, the reinforcement or steel structure in the reinforced concrete structure can be used as a lightning arrester to intercept lightning flash discharge. Generally, it has little impact after being hit by direct lightning. It should be noted that the non-metallic objects caught fire caused by lightning and the secondary injury caused by the falling of wall tiles on the surface of buildings. However, this problem is not easy to solve. For example, it is impossible to wrap steel balls on the Oriental Pearl Tower in Shanghai as a transmitting antenna, so that its antenna will not transmit signals. The cause of the lightning strike in Shanghai Oriental Pearl Tower is that the insulation layer made of glass fiber reinforced plastics is non flame retardant material. In order to prevent lightning and fire, the insulation layer can be replaced with flame retardant materials.
Guan Xiangshi said that lightning strikes on high-rise buildings still belong to low probability events, and we can’t worry too much, but we can’t relax our vigilance.
Lightning protection of high-rise buildings should be repaired both inside and outside
Lightning protection of buildings is divided into external lightning protection and internal lightning protection. The external lightning protection devices are lightning arrester, down lead and grounding device, and the internal lightning protection devices are shielding, equipotential connection, surge protector, etc. Guan Xiangshi believes that the external lightning protection work of high-rise buildings in China is relatively good, while the internal lightning protection work is relatively weak. The lightning protection of electrical and electronic systems in buildings should become the focus of lightning protection of high-rise buildings.
Guan Xiangshi said: “at present, people can hardly live without electronic products. Electrical and electronic equipment are very delicate and sensitive. If they suffer from direct lightning or lightning electromagnetic pulse, it is easy to cause damage to electrical and electronic systems and fire, and their direct and indirect losses will be great. At present, lightning protection measures inside buildings are easy to be ignored.”
Statistical analysis and a large number of lightning disaster investigations show that most lightning casualties and lightning disasters are caused by the failure to take lightning protection safety measures and imperfect lightning protection devices. The imperfect lightning protection device of existing buildings is the main cause of lightning accidents in buildings.
Guan Xiangshi suggested that in order to avoid and reduce the loss of lightning disasters, qualified professional lightning protection testing institutions should regularly test schools, hospitals, hotels and high-rise buildings; During the design and construction of lightning protection devices, the construction unit shall comprehensively consider the geological, soil, meteorological, environmental, characteristics of protected objects, lightning activity law and other factors, and adopt safe, reliable, technologically advanced, economical and reasonable design and construction, as well as lightning protection equipment, devices and equipment whose technology and quality meet national standards, Ensure the safety of building lightning protection and the safety of people’s lives and property. In addition, we should strengthen the popularization of the public’s scientific knowledge of lightning protection, improve the public’s awareness of lightning protection and the ability of disaster prevention and self rescue, so as to stay away from lightning disasters and take care of life.


Post time: Mar-05-2022