Photo: The 15-meter-class super-large shield machine "Zongheng" slowly enters the shaft

On June 5, the under-construction East Section of the North Cross Passage Project completed another important milestone: as the 15-meter-class super-large shield machine "Zongheng" slowly entered the shaft, it marked the successful breakthrough of Section VIII of the North Cross Passage new construction project.

Section VIII of the North Cross Passage new construction project is invested in and constructed by Shanghai Chengtou Highway Investment (Group) Co., Ltd., and jointly undertaken by Shanghai Tunnel Engineering Co., Ltd. of Tunnel Holdings and Shanghai Urban Construction Municipal Engineering (Group) Co., Ltd. This section includes two running tunnels: Huangxing Road Shaft–Yangshupu Port Shaft and Yangshupu Port Shaft–Anguo Road Shaft, with a total length of 2,842 meters.

The "Zongheng" shield machine was launched from the Huangxing Road Shaft in December 2021 and arrived at the Yangshupu Port receiving shaft in July 2022. After a short break, in September 2022, the "Zongheng" shield machine was launched for the second time and today successfully completed the final goal of excavation for the Yangshupu Port Shaft–Anguo Road Shaft running tunnel.

Underground crossing in the busy central urban area, with many buildings and structures and dense pipelines, became a difficulty for the shield tunneling. From November 18, 2022 to November 21, 2022, the "Zongheng" shield machine passed beneath the operating Rail Transit Line 18, ultimately advancing 21 rings within 65 hours to complete the crossing, creating the record for the smallest deformation of rail transit throughout the entire crossing process since the construction of the North Cross Passage.

From April 19 to April 24, 2023, the shield machine successfully crossed beneath Rail Transit Line 4 again at the intersection of Zhoujiazui Road and Baoding Road, achieving four national records for a 15-meter-class shield machine passing beneath rail transit: smallest clearance, largest slope, sharpest curve, and smallest angle. At that time, the "Zongheng" crossed Rail Transit Line 4 for a total of 28 rings, with a crossing length of 56 meters, the longest construction distance of the entire North Cross Passage passing beneath rail transit. Through careful planning, the project construction team successfully controlled the crossing within the crossing window period stipulated by the rail transit operator, ensuring the safety of subway operations.

The North Cross Passage new construction project has a total length of about 19.1 kilometers. Among them, the underground tunnel section is about 14.7 kilometers long, the west section tunnel is 7.8 kilometers long, and the east section tunnel is 6.9 kilometers long. Huang Guobin, Deputy Party Secretary and Chairman of Chengtou Highway Group, introduced that the east section of the North Cross Passage is currently mainly carrying out shield tunneling, and the two shield machines undertaking the excavation tasks, "Jiangong" and "Zongheng", are both "advancing" as planned. After "Zongheng" completes its excavation task, "Jiangong" is also planned to enter the Anguo Road Shaft at the end of July to join "Zongheng". "At present, the main line shield tunneling of the east section of the North Cross Passage has completed 90%, and the open-cut section has completed 60%. It is expected that the main line structure of the east section will be completed by the end of this year, laying the foundation for completion and opening to traffic in the first half of next year."