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Substandard thin steel bars banned

2010-09-06 07:55

XI'AN - Construction authorities in Xi'an, capital of Shaanxi province, over the weekend ordered builders to stop using thin steel bars that do not meet construction standards.

Liu Lin, director of the construction and real estate management department under the Xi'an Industry and Commercial Administration Bureau, told China Daily on Sunday that his colleagues found in a recent inspection that a number of steel bar processing plants in the city illegally manufactured bars too thin.

"By making the steel bar thin, both the processing plants and the construction firms decrease their cost, but these bars will do harm to the quality of the building projects," Liu said.

According to local construction and real estate management officials, the processing plants are pulling the steel bars longer and thinner than the minimums required. The 10 mm bars are pulled to 9 mm in diameter, and the 8 mm diameter bars are only 6 mm thick.

The State standards for the processing of the steel bars stipulates that the pulling rate of the steel bars cannot be more than 4 percent. The 10 mm diameter steel bars, for example, cannot be pulled to less than 9.6 mm in diameter.

An incomplete investigation by local authorities showed that more than 100 processing plants engage in such illegal practices, which has become the unspoken rules for the company leaders to gain better profits.

According to Dai Jun, an engineer with Shaanxi Provincial Building Research Institute, one ton of 10 mm diameter steel bars should be 1,620 m in length, but when it is pulled to a 9-mm diameter, 1 ton of the steel bars is 2,000 m in length. The extra part is valued at some 760 yuan ($113).

Statistics by China Real Estate Information Group showed that some 11.98 million sq m of building projects are under construction in Xi'an. Xi'an Construction Engineering Quality Supervision Station found in a recent inspection that nearly 10 percent of some 1,000 construction sites used the thin steel bars.

An unnamed owner of a processing plant said that he gave some money to the project supervisors at the construction sites, who then allowed his thin steel bars to pass inspection.

According to Wu Chengcai, general engineer in Shaanxi Provincial Building Research Institute, stretching the steel bars damages them, causing them to become brittle and weak. These bars' resistance to earthquakes is much less than the thicker, standard steel bars.

"When a building suffers great external force such as an earthquake, the stronger, standard steel bars will 'stretch' as the building suffers the damage, thus slowing the process of its collapse for people to escape. However, the buildings with the substandard, thin steel bars will collapse very quickly," Wu said.

In order to better protect the building quality, Xi'an city and Shaanxi provincial governments issued documents to urge the supervision of steel bar processing quality and ordered all construction projects' supervisors to pay close attention to the steel processing and ensure the quality of the steel bars.

Duan Enchao, an official with Xi'an Construction Engineering Quality Supervision Station, said that the illegal processing has been banned and thin steel bars are being stopped from entering any construction site. The station has also confiscated the substandard steel bars found at construction sites.

Xinhua contributes to this story.

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