SHANGHAI: Concerns are being raised at strong winds damaging skyscrapers in Shanghai.

Tian Wei, from Shanghai Architecture Association, said three business districts in the downtown area Lujiazui, the block around Hengshan Hotel and another district off Huaihai Road were most at risk.

According to statistics in 2001, Shanghai had the largest concentration of skyscrapers in the world. And the number of skyscrapers in the city has grown considerably since then. Shanghai now boasts 2,000 buildings designated as "tall," and more than 140 of them are above 100 metres.

But wind currents can often form mini whirlwinds around skyscrapers in densely developed areas.

Wind speeds also become much stronger in narrow roads between high buildings.

When the two phenomena combine, the effects can be potentially destructive, according to Tian.

Buildings higher than 150 metres are the most susceptible to the problem, he added.

Cheng Mu, deputy chief engineer with Shanghai Xian Dai Architecture Design (Group) Co Ltd, said the winds could cause huge levels of destruction in areas around skyscrapers.

As many of the skyscrapers in Shanghai adopt glass curtain walls, they could become dangerous if affected by the problem of strong winds, according to Li Jie, the director of Shanghai Institution of Disaster Prevention and Relief.

Broken shards falling down from glass walls are sometimes witnessed during the typhoon season.

In early 2005, Shanghai municipal government named skyscrapers as one of the biggest potential dangers for the city.

Mu said the potential problems surrounding skyscrapers could be reduced if the height of them was limited, and the distance between them increased. Shanghai drew up rules covering the two aspects three years ago.

The government carefully scrutinizes construction projects that are proposed to be more than 130 metres in height or be erected in built-up areas.

Yang Hairong, vice-general engineer with Shanghai Urban Planning Administration Bureau, said that the government had included skyscrapers in a list of areas of concern in a comprehensive disaster-prevention plan.

Source: China Daily