The main bridge of the Qinglongmen Grand Bridge in East China’s Zhejiang Province was successfully closed on June 23. It is the world’s longest three-tower cable-stayed bridge with steel box girders.
The bridge is jointly built by China Railway Construction Bridge Engineering Bureau Group Co., Ltd. and CRCC Harbour & Channel Engineering Bureau Group Co., Ltd., which are both subsidiaries of China Railway Construction Corporation Limited (CRCC).
The closure marks the completion of the bridge’s primary structure, paving the way for the scheduled opening of phase II of the province’s Liuheng Highway Bridge at the Zhoushan Port in Ningbo.
Spanning the Qinglongmen waters off Zhoushan, the 2,212-meter-long bridge connects Fodu Island in Zhoushan and Meishan Island in Ningbo, boasting two main spans of 756 meters each.

The main bridge of the Qinglongmen Grand Bridge is successfully closed on June 23, 2026. [Photo/sasac.gov.cn]
The closure involved the simultaneous hoisting of two steel-box girders, each measuring 4.5 meters in length and weighing 82.8 metric tons. The construction site is characterized by extreme hydrodynamic conditions, including strong winds for over half the year and thick fog for almost 40 days per year. Furthermore, the navigation channel beneath the bridge must remain clear to accommodate 50,000-ton container vessels.
Considering these challenges, the installation team engaged in 48-hour continuous dynamic monitoring prior to the closure. Leveraging real-time temperature data, engineers executed precision milling of the closure gap to ensure seamless alignment and embedment of the segments.
The construction team of the Qinglongmen Grand Bridge overcame multiple world-class technical hurdles. Notably, the main pier's steel cofferdam utilized an innovative "permanent-temporary integration" design. Functioning as a cofferdam during construction, it transitions into a permanent anti-collision barrier upon completion.
As a pivotal sea-crossing link of the Liuheng Highway Bridge project, the Qinglongmen Grand Bridge project will connect Ningbo and Zhoushan. Upon completion, it will finally bring expressway access to the islands of Meishan and Liuheng in Zhoushan and Fodu Island in Ningbo, marking the end of their isolation from the national expressway network.
This development will further streamline the spatial layout of the Zhoushan Archipelago New Area and foster the integrated development of ports and industries across the three islands.
(Executive editor: Zuo Shihan)