August 19，At the construction site of Zhujiangkou Tunnel of Shenjiang Railway，China's deepest submarine tunnel shield machine jointly built by China Railway Construction Heavy Industry and China Railway 14th Bureau“Shenjiang No.1”Successfully reached 106 meters under the sea.，Complete the excavation task of 3590 meters，This is the deepest underwater tunneling record of China's shield machine.，It is also the deepest record of China's high-speed rail shield tunnel reaching the seabed.。

“Shenjiang No.1”The shield machine reaches 106 meters under the sea.

The total length of Zhujiangkou Tunnel is 13.69 kilometers，It is a key control project of Shenjiang Railway.。“Shenjiang No.1”The shield machine excavated 3590 meters from Dongguan to Nansha, Guangzhou.。During tunneling，The shield machine passes through several main channels，It passes through 13 kinds of strata successively、Five kinds of composite geology，Full-face hard rock tunneling up to 2.75 kilometers，The highest strength of granite is 124.6 MPa，It also continuously crosses 17 fault zones and branches.，Complicated hydrological and geological conditions of the interval project，It brings great difficulty to the project.。

Schematic diagram of the tunnel profile

The lowest point of the shield section of the tunnel is 106 meters below the water surface of the Pearl River Estuary.，An area equivalent to the size of a fingernail bears 10.Six kilograms of pressure.，There is no engineering experience and design standard with the same conditions for reference in China.。

“Shenjiang No.1”Shield machine rolled off the production line of China Railway Construction Heavy Industry

For construction problems，“Shenjiang No.1” The shield machine is equipped with a constant-Heavy-duty composite cutterhead with pressure、High load bearing main drive、A series of intelligent systems such as synchronous single and double liquid grouting，Maximum pressure bearing capacity up to 12bar，Thereby greatly improving the adaptability under the working condition of seabed ultrahigh water pressure.，Ensure that the shield machine is under ultra-high water pressure、Super deep burial、The unfavorable geological section with developed fissures is continuous、Stable、Safe tunneling。

Shenjiang Railway is located in the center of Guangdong-Hong Kong-Macao Greater Bay Area.，It's the whole country“Eight vertical and eight horizontal”The high-speed railway network is an important part of the coastal corridor.，After completion and opening, it is conducive to creating a half-hour life circle in the Guangdong-Hong Kong-Macao Greater Bay Area.、Economic Circle，Shenzhen's Qianhai Free Trade Zone and Guangzhou's Nansha Free Trade Zone will be interconnected by high-speed rail for half an hour.。