On January 4, 2023, the super large diameter slurry balanced shield machine "Pioneer" jointly developed by Guangzhou Communications Investment Group, China Railway 14th Bureau and Railway Construction Heavy Industry will be launched in Changsha and will be applied to the tunneling construction of Haizhu Bay Tunnel Project, a key project in Guangdong Province and Guangzhou City.

The total length of Haizhuwan Tunnel is 4.35 kilometers, including 2077 meters of shield section and 14.5 meters of segment outer diameter. It is the first super large diameter municipal shield tunnel in the Pearl River basin. The shield construction crosses the soft and hard composite red bed geology in the Pearl River Delta region for a long distance, the stratum fracture fracture zone twice, and the Pearl River Channel twice. The maximum buried depth of the shield section is 48 meters, and the rock strength is up to 50 MPa. It is one of the projects with high requirements for construction environment and construction level in Guangzhou and even China's super large shield tunnel projects.

The "Pioneer" shield machine that went off the production line this time has a maximum excavation diameter of 15.07 meters, a total length of 130 meters, and a total weight of about 4300 tons. In view of the complex geological problems and the technical problems of the cutter head caking, the configuration has been upgraded. By increasing the opening rate of the cutter head of the shield machine, configuring hobs, reducing the blade spacing, ensuring the rock breaking ability of the blade, the cutting face is more dense and symmetrical. The cutter head is also equipped with sensing elements, which can sense the working state of the cutter in real time. Combined with the front and rear telescoping function of the main drive, it provides a more advanced intelligent means for the shield machine to "replace teeth" in time.Editor/Ma Xue