Project Description:

Hong Kong-Zhuhai-Macao Bridge connects Hong Kong in the east and Zhuhai and Macao in the west. It is currently the world's longest cross-sea project integrating Bridges, islands and tunnels. It is extremely difficult and has been praised by the Guardian as one of the "Seven wonders of the New World". The project was jointly built by Guangdong, Hong Kong and Macao for the first time, and the construction lasted nine years, with a total investment of more than 100 billion yuan.

The Island Tunnel project is a controlling project of the main project of  Hong Kong-ZhuhaiMacao Bridge, which mainly includes the 6,700m offshore submerged tube tunnel and two offshore deep water artificial islands with an area of 100,000 m2. It is a world-class major project integrating the island tunnel in the offshore sea. The new integrated development equipment is adopted in the construction of the submerged tube tunnel in the outer sea, which reflects that China's independent innovation has reached a new height. It is the first time to creatively propose, design and successfully apply the semi-rigid pipe joint in deep sea, which has accumulated valuable experience for the design and construction of deep-sea submerged pipe tunnel in the world.

Technical Highlights:

1. Creatively put forward the design scheme of semi-rigid tube sections for deep-sea immersed tube tunnels, which is a milestone development in the world's immersed tube tunnel design and construction technology.

2. Based on the 120-year service life of the concrete structure of the island tunnel project, it is the first in China to carry out quantitative durability design, and put forward quantitative requirements on the material or structural indexes of the components, which are successfully applied.

3. Innovative immersed pipe section installation technology, adopting self-developed "deepwater unmanned sinking and placing system", including mooring positioning, ballast control, automatic pulling and closing, measurement control and in vivo fine-tuning and other systems, which avoids the risk of underwater operation by divers.

4. Proposed the concept of composite foundation for the foundation treatment of artificial island, and at the same time, proposed and utilized the index program of double control of penetration and elevation of PHC piles, which saved the project construction period and cost.