"The glass curtain wall of the Ningbo Global Center exploded again", read a message posted by a microblog user called "Feng Feng sky" at 8 a.m. on 27th August.
This is the third time that the glass curtain wall of the Ningbo Global Center has exploded after the first time in October, 2010 and the second time in July, 2011.
According to a police officer on the scene, the toughened glass exploded and fell down from the 36th floor of the building. The exploded glass broke into tiny pieces, causing a shower of "glass rain". Fortunately, no casualties were reported in the incident.
Ningbo Global Center is located in the Sanjiangkou of Haishu district, near to Tianyi Plaza, Tesco and FM Food Square. Accidents of this kind can cause unimaginable damage, especially in a prosperous commercial center bustling with cars and people.
Citizens expressed their fears about this kind of accident, which is not exclusive to Ningbo. In May, 2011, more than 50 cars parked at Shanghai Lujiazui Financial Centre were hit by the "glass rain" after a glass curtain wall exploded. Another accident happened in Hangzhou when falling glass injured a 19-year-old girl, whose left leg was amputated after the accident.
What causes such explosions? According to the manager of the Ningbo Rongyao Real Estate Co,.Ltd, the explosion rate of toughened glass is 0.3%. This is because one of the components called nickel sulphide will swell or shrink with changes in temperature. However, explosions occur as the changing shape of the nickel sulphide doesn't match the deformation of the glass.
Another potential reason may be strong wind, as the exploded glass was at the north side of the building, the windward side, said the manager.
