In recent years, to build the "Greater Bay Area One-Hour Living Circle" and benefit Zhuhai residents as well as people traveling across the Pearl River Delta, Zhuhai has invested in numerous transportation projects connecting key urban areas and linking Zhuhai with neighboring cities, including roads, bridges, and tunnels in various forms, such as the Xianghai Bridge, Jinhai Bridge, Huangmaohai Bridge, Zhuhai Airport Intercity Railway, Xingye Expressway, and Hegang Expressway. Among them, Zhuhai's deepest tunnel—the Shizimen Tunnel—is a key component of Zhuhai's major transportation projects!

It is understood that the Shizimen Tunnel project is undertaken by China Construction Third Engineering Bureau. The project has a total length of 2.8 km and is located in Nanwan Urban Area and Hengqin New Area of Zhuhai. It starts from Rongyue Road in Hengqin in the south, crosses the Maliuzhou Waterway, and extends north to Huizhan 4th Road and Nanwan Avenue in Xiangzhou. The main line is designed as a dual four-lane road with a design speed of 40 km/h.

Due to environmental conditions, the excavation depth of the launching shaft on the south bank of the tunnel project reaches 36 meters, making it Zhuhai's deepest tunnel. Its foundation pit is called "the first deep coastal foundation pit in the Zhuhai area with the greatest construction difficulty and the deepest excavation." Construction faces five major technical difficulties: extremely poor geological conditions, high difficulty in construction involving railways, strong corrosiveness of coastal groundwater, numerous underground obstacles, and difficult rock excavation near the intercity railway and existing buildings.

To solve the above technical difficulties, China Construction Third Engineering Bureau adopted targeted and effective measures and applied world-class advanced technologies that are leading in China and even globally, ultimately effectively achieving the project's construction objectives.

For example, in response to the difficulty of construction involving railways, China Construction Third Engineering Bureau actively joined forces with industry experts to tackle technical challenges. While using the MJS method (also known as the all-directional high-pressure jet grouting method) to fully and reasonably grout and reinforce the soil, it followed the principle of time-space effects and carried out reasonable layered, block-by-block, and alternate-bay excavation of the foundation pit soil, ultimately controlling deformation and displacement within a reasonable range.

In addition, due to numerous underground obstacles and difficult rock excavation, blasting technology was also comprehensively applied in this project. Mechanical methods such as hydraulic splitters and mountain-cutting stone saws, as well as chemical methods using static agents for reaction blasting, all played important roles in the project excavation.

In addition, due to numerous underground obstacles and difficult rock excavation, blasting technology was also comprehensively applied in this project. Mechanical methods such as hydraulic splitters and mountain-cutting stone saws, as well as chemical methods using static agents for reaction blasting, all played important roles in the project excavation.

It is worth mentioning that the tunnel project simultaneously adopts the open-cut method and the shield tunneling method. Among them, the shield tunneling section (the section crossing the Maliuzhou Waterway) is about 940 meters long and is arranged in upper and lower levels, each equipped with a roadway and a sidewalk (also serving as an evacuation passage).

The tunnel project's technical precision controlled project construction and avoided risks, ultimately achieving the successful bottom sealing of the launching shaft in June last year, laying a solid foundation for undersea shield tunneling. The tunnel project's conception also well balances safety and transportation convenience. The project fully demonstrates China Construction Third Engineering Bureau's advanced and sophisticated technology and strong project construction execution capabilities from multiple perspectives!

The project is still being intensively arranged for construction and advancement, and is expected to open to traffic in June 2022. By then, it will connect the Hengqin New Area Financial Island and the Shizimen Convention and Exhibition Center area, greatly improving Zhuhai's traffic flow and enhancing urban vitality!

At present, China Construction Third Engineering Bureau is still participating throughout the construction of many important landmark projects in Zhuhai. In addition to the Shizimen Tunnel, China Construction Third Engineering Bureau has also undertaken the construction of Zhuhai's largest municipal elderly care institution—the Nanping Municipal Elderly Care Institution—as well as many other landmark buildings in multiple fields and types.

Behind these landmark buildings, what unknown efforts and sweat, or perhaps interesting stories, are there? Please continue to follow Sina Guangdong Zhuhai's news feature "China Construction Third Engineering Bureau in Zhuhai | One Landmark, One Story," which will continue to bring updates and interpretations throughout July!