At 9:58 on February 8, the Wuhan Yangsigang Yangtze River Bridge completed a major engineering milestone: its pilot cable completed the high-difficulty "threading the needle" 2 hours ahead of schedule, spanning the 1,700-meter-wide river and successfully "connecting" the main towers on both banks. This marks that the world's longest-span double-deck highway suspension bridge has officially entered the superstructure construction phase.
The Yangsigang Yangtze River Bridge is a double-tower, double-deck, earth-anchored steel truss girder highway suspension bridge that crosses the Yangtze River in a single span, with a main span of 1,700 meters. It is also the first double-deck highway bridge over the Yangtze River. The starting point is at the Hanyang Guobo Interchange and the end point is at the Wuchang Batan Interchange. The pilot cable crossing the river is the first step in the superstructure construction of a suspension bridge. After the pilot cable crosses the river, high-altitude operations on the bridge no longer require shipping closures. The construction team will use the pilot cable to pull back and forth to erect the "aerial trestle" catwalk, thereby installing the main cables.
The pilot cable crossing was planned to require a 4-hour shipping closure. On the 8th, the sky was clear and the wind and waves were relatively calm. At 7:56, the tugboat set sail from the Hanyang bank. At 9:58, with perfect coordination between the tugboat and the winches on both banks, the pilot cable reached a height of 33 meters above the river surface and successfully "crossed the river." Because the pilot cable crossing went very smoothly, the water traffic control was lifted at 10:20, 2 hours earlier than expected.
Li Luping, deputy manager of the Yangsigang Bridge General Contracting Department of China Railway Major Bridge Engineering Group, explained that the entire process was like "threading a needle." The two main towers on the Hanyang and Wuchang banks, each over 240 meters tall and nearly 80 stories high, were like two "giant needles," and the pilot cable—26 millimeters in diameter, 6.2 kilometers long, and weighing 16.6 tons—was the "thread." It passed through the tower-top gantry, was tied to the front of the tugboat, and under the tugboat's traction, this "thread" spanned from the Hanyang bank to the Wuchang bank. The winches on both banks paid out and reeled in the cable, lifting the pilot cable to a height of 33 meters above the river surface, reaching a safe navigation distance.
As a super project on Wuhan's Yangtze River main axis, the Yangsigang Yangtze River Bridge is scheduled to be completed and open to traffic in 2019.
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There are many methods for a suspension bridge pilot cable to cross a river. At present, methods used for pilot cables of long-span suspension bridges in China to cross rivers or deep mountain gorges include rocket launching, hot air balloon traction, airship traction, helicopter traction, and drone aircraft traction. The pilot cable crossing of the Yangsigang Yangtze River Bridge had the conditions for a one-time tugboat tow to the designated position, which was economical and convenient. If a drone were used, it could not pull the 16.6-ton pilot cable in one go, and the pilot cable would also need to be replaced multiple times.