Construction of the Shuangyumen Bridge reached a major milestone on March 10 in Zhejiang Province, as workers began installing the main cables for what will be the world's longest-span single-span steel box girder suspension bridge. The successful delivery of the first cable strand to the Fodu anchorage marks a pivotal transition in the project, clearing the way for subsequent cable-staying and girder lifting operations.
As the "backbone" of any suspension bridge, the main cables are responsible for distributing the weight of the entire bridge deck. The Shuangyumen Bridge, a centerpiece of the Ningbo-Zhoushan Port Liuheng Expressway (Phase II), features two massive cables. Each measures roughly 3,176 meters and is composed of 127 high-strength, corrosion-resistant steel strands, with each individual strand weighing approximately 97 metric tonnes.
The initial "reference strand" serves as a precision benchmark for the rest of the structure, demanding surgical accuracy during installation. To overcome the volatile offshore conditions and technical complexities, the CRCC engineering team utilized a dual-line reciprocating traction system to guide the strands across the main towers. To mitigate the effects of thermal expansion and contraction, the crew followed a rigorous "daytime hauling, nighttime calibrating" schedule to ensure the bridge's geometry remains perfect.
Once operational, the bridge will significantly enhance the transport network across the southern Zhoushan islands, fueling the integration of the Ningbo-Zhoushan Port and driving high-quality economic growth throughout the region.