On February 21, 2023, a Tunjima shield machine with the pattern of a brave tiger shark painted on the cutter head was completed and rolled off the production line smoothly.

This is a domestically produced large-diameter mud-water balance shield machine jointly built by China Railway 14th Bureau and China Railway Construction Heavy Industry Group. It will be used in the construction of the Shantou Bay Tunnel on the Shantou Guang'ao Port Area Railway, and will soon start a journey through the sea.

Shantou Guangao Port Railway is located in Shantou City, Guangdong Province. It starts from Shantou Station of Guangmeishan Railway in the north and ends at Guangao Port in the south. The Guangzhou-Macao Port Area Railway Line 1 has a total length of 17.116 kilometers, including a tunnel, two bridges and other construction content. The Shantou Bay Tunnel is a key and difficult control project of the project, with a total length of 9965 meters, of which the shield section is 2990 meters long. The segment has an outer diameter of 12.9 meters and an inner diameter of 11.8 meters.

Railway layout plan of Shantou Guang'ao port area

The shield section of the Shantou Bay Tunnel passes through complex strata such as soft soil, uneven hardness, boulders, full-section hard rock, and fault zones. There are 11 fault fracture zones in the sea area of Shantou Bay, and the construction of high water pressure and shallow overlying soil is extremely difficult. big. The tunnel passes through many important structures such as the subgrade of Shenhai Expressway, and the construction risk is high.

Since the start of the tunnel, the project department has organized internal expert seminars and shield machine selection analysis meetings for many times, and invited well-known domestic experts to review the design of the shield machine. It has rich experience in the construction of shield tunnels across rivers and seas for many years in China Railway 14th Bureau On the one hand, it has laid a solid foundation for the targeted design and optimization of the shield machine manufacturing and the safe and efficient tunneling of the sea-crossing tunnel.

Gujima shield machine

The excavation diameter of the cutter head of the Tunnel Tunneling Machine on the Gudao Island is 13.42 meters, the total length of the shield machine is 126 meters, the weight of the whole machine is about 3,300 tons, and the total installed power is 9,300 kilowatts. The shield cutter head has the functions of normal pressure tool change, hob exchange, hob wear detection, speed detection, and temperature detection. In order to deal with the problem of low construction efficiency in hard rock formations, the distance between cutterheads and cutters of the shield machine has been further reduced, and pressure hobs have been added to help improve rock breaking efficiency. The cutter head is equipped with a total of 185 cutters, of which 89 can be replaced under normal pressure, realizing the "full coverage" of the cutter head's excavation trajectory.

Technicians operate the Sujima

Tiger sharks make waves in the sea, heavy weapons are listed, and the coating of the cutter head of the shield machine on the island of Gudao reflects the characteristics of local culture. It is understood that Shantou, also known as Yudao. Anchovy is a small, round fish with spots, belonging to a type of shark called anchovy. Shantou City is located on one side of the Tuoji River and surrounded by water on three sides. It used to be a peninsula in history. In the past, the bay was rich in sharks, so it is called Tuo Island.

The Guang-Mao Port Railway is a convenient channel for Shantou Port and an important way to connect the hinterland. At the same time, it is reserved to undertake part of the passenger transport function along the line. After the completion of the project, on the basis of comprehensively improving the collection and distribution capacity of the Guangzhou-Macao Port Area, it will strengthen the connection between the north-south regions, strengthen the connection with the Guangdong-Hong Kong-Macao Greater Bay Area and the Haixi Economic Zone, and improve the layout of the regional intercity transportation network. Editor / Zhao E