On May 1, 2023, the Dalian Bay Submarine Tunnel, the first cross-sea immersed tube tunnel in northern China, was completed and opened to traffic. This tunnel is located in the sea area of Dalian Bay to the east of Dalian, from Dalian Diamond Bay in the north to Dalian Donggang Business District in the south, with a total length of 5.1 kilometers. The construction standard is a two-way six-lane urban expressway with a design speed of 60 kilometers per hour. The service life is 100 years.

During the four-year construction process, the project construction party overcame the difficulties of complex geological conditions, high construction risks, and many technical difficulties, successfully solved the century-old durability problem of marine concrete structures in cold regions, and realized large-scale ships and underwater cable sockets. Localization of core equipment and technology, and new structures and technologies such as "jacking segmental" final joints, permeable shore structures, and full floating leveling of crushed stone beds are applied to immersed tunnel projects.

The Dalian Bay Submarine Tunnel has pioneered the construction of large-scale cross-sea immersed tunnels in cold regions in China, and has formed a core technology with independent intellectual property rights, which has strongly promoted the progress of my country's cross-sea immersed tunnel construction technology, and has contributed to the construction of immersed tunnels in the world. contributed to China's strength. Sun Zhu, deputy chief engineer of Dalian Bay Submarine Tunnel Co., Ltd., said.

The Guangming Road extension project connected to the Dalian Bay Submarine Tunnel was completed and opened to traffic on the same day. Together with the subsea tunnel, it forms a fast track running through the north and south of Dalian City, and builds a "5-minute convenient living circle" on the north and south sides of Dalian Bay. This is of great significance for alleviating traffic congestion in the central urban area of Dalian, expanding the space for urban development, and promoting the integration of the two sides of Dalian Bay.Editor/Ma Xue