Beijing will replace a worn-out overpass by rebuilding a new 1,300 metric ton bridge within 24 hours on Friday night, which will set a new record in China for taking the shortest time to rebuild an overpass in a heavy-traffic downtown area, the Beijing Municipal Commission of Transport said on Tuesday.

The Sanyuanqiao Overpass and the section of Jingshun Highway under the overpass will be closed from 11 pm on Friday to Saturday midnight for the work, said Hou Xiaoming, deputy director of the commission's road management department.

Sanyuanqiao, on the northeast section of the Third Ring Road, was completed on Sept 21, 1984, to link the city with Beijing Capital International Airport. As one of the country's largest overpasses and one of the busiest traffic hubs in Beijing, Sanyuanqiao handles more than 200,000 vehicles and buses from 48 routes carrying 726,000 passengers each day, according to Qin Dahang, an engineer at the Beijing General Municipal Engineering and Research Institute Co Ltd. Therefore, the shorter the project takes, the better for commuting residents, he said.

The current Sanyuanqiao Overpass, weighing 1,600 tons, will be cut into pieces and removed on Friday and Saturday. Two trucks,each able to support 1,000 tons, will move the new overpass, made of steel and operational for 100 years, as one piece to reinforced supports on the overpass to reconnect the two ends of the Third Ring Road.

During construction, private cars will not be allowed to pass and buses will traverse the area on a roundabout that has been under construction since September.

Hou Xiaoming, deputy director of the commission's road department, said building an overpass in downtown areas usually takes a few months to complete. The project will only take 24 hours with sophisticated design and preparation.

"It's China's first time to adopt 1,000-ton supporting machines to replace such a giant overpass. It can be a successful example for other cities to follow in downtown areas prone to traffic jams," Hou said.