Pivotal Beijing cloverleaf junction reinforced

Workers on Sunday morning finished reinforcing an old pivotal cloverleaf junction in a downtown Beijing commercial zone using a new prefabricated steel structure.

The Sanyuanqiao cloverleaf junction was closed for overhaul this weekend with the aim of reinforcing the structure without paralyzing traffic flow.

Workers used global positioning systems, laser positioning and robots to place the new structure at around 11:30 a.m. Sunday.

The most challenging part of the overhaul, the replacement of the 1,300-tonne bridge structure, began at 11 p.m. Friday at the junction on the northeastern Third Ring Road.

The process was initially planned to last 24 hours, but the central beams of the old bridge were in much worse condition than expected, requiring extra dismantling work. Beijing Municipal Commission of Transport had to extend a 24-hour traffic ban to 30 hours.

Replacement of the bridge structure cost 39 million yuan (6.1 million U.S. dollars), according to the commission.

The Sanyuanqiao cloverleaf junction is a major congestion point on a tollway to the airport. It also links two pivotal highways: the Third Ring Road and the highway linking downtown Beijing with the outlying Shunyi District.

Built in 1984, the bridge was in poor shape and needed reinforcement for safety reasons. Endi