On March 14, 2026, the Guangzhou Yuzhu Tunnel project, constructed by China Railway 18th Bureau, successfully completed the first batch of pipe section sinking and installation. This tunnel is the longest inland immersed tube tunnel under construction in southern China, and the engineering construction has made breakthrough progress. The Yuzhu Tunnel is about 2.6 kilometers long, starting from Xingang East Road in the south and crossing the the Pearl River twice in the form of immersed tube tunnel. The project adopts a construction mode of onshore prefabrication and underwater installation, which is like assembling building blocks, precisely connecting giant pipe sections to form the main structure of the underwater tunnel.

The total length of the immersed tube section of the tunnel is 935 meters, with a total of 9 large pipe sections, prefabricated and installed in three batches. The E3 pipe section sunk this time is the last section of the first batch of immersed pipes. The pipe section is 105.5 meters long, weighs about 28000 tons, and has a floating distance of about 3.6 kilometers. The overall floating and installation time is two days. In the the Pearl River waters with narrow channels and complicated water flow conditions, it can be called the river bottom threading to achieve the precise positioning of such huge components.

As the inland immersed tube tunnel with the smallest curve radius in China, Yuzhu Tunnel faces multiple technical challenges during the construction process. The project team has carried out research and development on key technologies such as prefabrication of Linjiang Island dry dock, crack control of large integral rigid pipe section full section pouring, long-distance towing under complex hydrological conditions, and attitude collaborative control. They have independently developed an "intelligent walking full section hydraulic template system" and built a smart construction site control platform, forming a complete technical system suitable for inland river immersed tube construction.

During the E3 pipe section floating installation period, faced with challenges such as long floating distance, narrow inland waterway, complex navigation environment, and the interaction between tides and runoff, the project department innovatively carried out the first domestic inland immersed tube floating simulation exercise to test the feasibility of the plan and the ability to coordinate emergency response. During the construction process, the project closely cooperates with relevant local departments to ensure that the passage of waterways is not affected through real-time monitoring, adjustment of navigation marks, and other measures, ultimately achieving millimeter level high-precision docking of pipe joints. Keywords: Yuzhu Tunnel, Immersed Tube Tunnel, Pipe Section Sinking

Next, the project team will make every effort to promote the prefabrication, floating and sinking of the second batch of 3-section pipe sections, as well as the construction of key nodes such as the Beidisha Island main tunnel, to ensure the high-quality advancement of the Yuzhu Tunnel. The Yuzhu Tunnel is an important node in Guangzhou's "Eastward Expansion and Southward Expansion" strategy. After the project is completed and opened to traffic, the Pazhou and Yuzhu Business Districts will be accessible in 5 minutes, which will ease the traffic pressure on both sides of the the Pearl River and drive regional economic development.Editor/Gong Ziwei