Major revamp makes Nanpu Bridge safe

Major maintenance work on Nanpu Bridge has been completed with hundreds of intelligent sensors installed to ensure its safe operation.

The work, which began in 2015, was carried out between midnight and 5am.

The main body of the multi-lane bridge, its entry and exit ramps in Puxi and the Pudong New Area, along with 11 other ramps have been renovated. The bridge deck, road foundation, lanes, safety facilities, traffic monitoring and electric systems have been renewed and upgraded, the Shanghai Engineering Design Institute said on Thursday.

The bridge, which opened in November 1991, was built to carry about 30,000 vehicles a day, though the actual figure is now near 120,000.

As a result, the first cable-stayed structure spanning the Huangpu River needs to be assessed to ensure its safe operation, according to the Shanghai Transportation Commission.

As part of the project, a total of 203 sensors were embedded across the bridge to monitor the condition of the structure, the institute said.

They can detect cracks and monitor the wind and temperature. Meanwhile, a new aluminum alloy mobile crane has replaced the original steel facility along with the elevator for maintenance workers to make it more efficient and safer to maintain the bridge.

New navigation signage has been installed on both sides of the bridge to complement the original five red lights to prevent collisions. 

The bridge’s former retractor device in the Puxi side has also been replaced. It sustained significant damage due to the land subsidence and heavy traffic during decades of continuous operation.