Sea sand alert halts Chinese projects

Claims have surfaced that unsafe sea sand has been found in ready-mixed concrete used on developments in Shenzhen, Guangdong province, China. The alerts have led authorities to order construction to stop on a number of projects, including the 660 m tall Ping'an Finance Center in Shenzhen.

Testing is underway on projects throughout Shenzhen, according to the city’s Housing and Construction Bureau, which said it had found 31 ready-mixed concrete production companies in violation of quality regulations. It said it ordered eight of them to suspend business for one year.

The plants were accused of producing concrete containing unwashed sea sand – considered an unfit building material due to the salt it contains. This can lead to the corrosion of rebar, leading concrete to crack and spall. Sea sand must be thoroughly washed before it can be used in ready mixed concrete.

China State Construction Engineering Corp (CSCEC), the contractor building the Ping’an tower, is reported to have said all materials used in its projects meet quality standards.

The Ping’an tower is being financed by developer Ping An Insurance, which is reported to have ordered the contractor to double check its concrete sources. Ping An Insurance also said it would co-operate with the investigation.

Designed by architects Kohn Pederson Fox, the 115 storey Ping'An International Financial Centre will be the tallest building in China and the second tallest building in the world when it is scheduled to be completed in 2015.