Built by China Railway 14th Bureau Group Co., Ltd., a subsidiary of China Railway Construction Corp, a super-large diameter shield machine positioned on the No 2 tunnel of the Tianjin Binhai International Airport for the Beijing-Tianjin Intercity Railway, started tunneling on April 10. This marks the official start of the first shield tunneling under an operational airport for the Beijing-Tianjin-Hebei high-speed railway.
The Beijing-Tianjin Intercity Railway is an important part of the "Beijing-Tianjin-Hebei on the track" project. The first phase of the project was completed and opened to traffic in 2022, and the second phase, which covers the Dongli to Binhai New Area section, is currently in full swing.
A super-large diameter shield machine positioned on the No 2 tunnel of the Tianjin Binhai International Airport for the Beijing-Tianjin Intercity Railway starts tunneling on April 10. [Photo/sasac.gov.cn]
The No 2 tunnel is 8,663 meters long, and has a shield section covering 7,720 meters, making it a crucial control project for the entire line. The tunnel passes under aircraft taxiways, highways, rivers and other high-risk areas, requiring strict control of settlement and presenting significant technical challenges.
To ensure the adaptability of the shield machine in complex strata, the construction team used the domestically developed super-large diameter shield machine for tunneling. The shield machine has an excavation diameter of 13.8 meters and weighs 2,600 tons. As one of the most advanced and intelligent shield machines for high-speed railway tunnels, it is equipped with a visualized system inside the excavation chamber for real-time observation of unidentified obstacles and an automatic monitoring system for cutter wear, ensuring precise cutter replacement.
During the construction process, the team took preemptive measures to reinforce key areas through ground grouting and formed a protective shell at the top of the tunnel. Additionally, they strictly controlled tunneling parameters, shield posture and enhanced ground settlement monitoring to minimize interference with the ground, ensuring the safe and smooth completion of the tunnel crossing.
In the future, after the full completion of the Beijing-Tianjin Intercity Railway, it will help Tianjin Binhai Airport become a large integrated transportation hub integrating railways, civil aviation and subways. The line will connect with other lines such as the Beijing-Tangshan and Beijing-Tianjin intercity railways, further improving the road network structure in the Beijing-Tianjin-Hebei region, providing more convenient and efficient travel services for the people in the region, and promoting the integrated development of the regional economy.
(Executive editor: Zhu Zeya)
