China Completes Installation of the Final Section of the 6,845m Undersea Tunnel in the Greater Bay Area, Guangdong Province, on June 11.
The event on June 11 marked the completion of the installation of the tunnel at both ends, according to the Guangdong Communications Group. This is the longest and widest steel-shell concrete undersea tunnel in the world, designed to accommodate two-way traffic with eight lanes, and is part of the 24km cross-sea project connecting Shenzhen and Zhongshan, as reported by CGTN.
The tunnel project consists of 32 sections, with each section measuring 165 meters in length and weighing 80,000 tons. These sections were transported along the Lingdingyang Channel using the Yihangjinan-1, a specially designed vessel.
Yihangjinan-1 is currently the largest and most advanced vessel in the world for transporting and installing undersea pipes, featuring the highest installation capacity, positional accuracy, and operational efficiency. This ship significantly increases the efficiency of pipe transportation and installation compared to traditional technologies. In addition to transporting and connecting the pipes, several critical stages of the undersea tunnel construction process include foundation treatment, trench excavation, and leveling.
The standard underwater pipes are deployed from the bottom of the ship to their designated positions, aligned with other pipes. The final pipe module, E23, required complex pre-manufacturing and features a mechanical joint. Once pipe E23 is positioned correctly, hydraulic jacks will push the joint connected to E23 outward, linking it to the end of pipe E24.
The specially designed vessel used to transport the final segment of the undersea pipe on June 8. (Photo: CFP).
“The undersea tunnel of the Shenzhen – Zhongshan Corridor utilizes precast pipes shaped like a giant drawer. This way, we can fully leverage the advantages of the equipment, reduce construction risks, and ensure the reliability of the project upon completion,” said Zhong Huihong, Deputy Director of the Shenzhen – Zhongshan Link Management Center.
The Shenzhen – Zhongshan Connection will play a crucial role in the development of the Guangdong-Hong Kong-Macau Greater Bay Area. The project’s bridges, artificial islands, and tunnels form a comprehensive transportation system both above and below water, considered one of the most challenging cross-sea projects in the world. The route is expected to be operational by 2024, reducing travel time between the two cities from about two hours to just 30 minutes.
