GBA Xili Shield Machine Rolls Off Production Line for Shenzhen Transport Hub Works
According to China News Service, the Xili Shield Machine, officially coded China Railway 1616, rolled off the production line in Shunde, Guangdong on 5 June. Developed entirely by China Railway Group, the ultra-large-diameter slurry shield will be deployed immediately for tunnel construction works linked to the new Shenzhen Xili Railway Station, a core node of the Guangdong-Hong Kong-Macao Greater Bay Area integrated transport network.
The new Shenzhen Xili Railway Station forms a pivotal part of China’s national eight vertical and eight horizontal high-speed rail network. Four intercity high-speed rail routes and multiple urban rail transit lines are scheduled to converge at the station. The 4-kilometre Xili Tunnel acts as the core connecting passage for internal and external traffic links at the hub and determines the overall operational timeline of the station.
On-site geological and construction constraints pose rigorous technical demands for tunnelling equipment. The tunnel reaches a maximum burial depth of 75.8 metres, passing through uneven weathered granite strata and deep weathered troughs with unstable soil structures. The tunnelling route crosses 21 critical surface infrastructures including existing national railways, urban highways and operational metro lines, requiring precise ground settlement control and stable internal pressure maintenance throughout excavation.
The bespoke shield machine has a cutterhead diameter of 13.9 metres, an overall body length of 135 metres and a total weight of 3,750 tonnes. Its design integrates targeted structural upgrades tailored to local complex geology. Engineers fitted the unit with a low-spacing wide-opening atmospheric composite cutterhead to cope with fractured rock strata, alongside a high-pressure screw conveyor direct discharge system and closed-loop zero-emission treatment modules to cut construction site pollution.
Intelligent monitoring systems are embedded across the machine’s core operating modules. Real-time cutter wear detection and multi-dimensional underground visualisation systems automate underground data collection, reducing manual inspection frequency and improving operational accuracy during high-risk underpass excavation. Compared with earlier large-diameter slurry shields used in Greater Bay Area rail tunnels, the updated visualisation architecture shortens abnormal risk response time by nearly 30 per cent.
The machine will undergo pre-operation debugging and site assembly in the coming weeks before formal tunnelling commencement. Optimised pressure balance technology will minimise ground disturbance above the tunnel route, protecting the structural safety of adjacent operating transport facilities. Completion of Xili Tunnel will streamline cross-city passenger and freight transfer efficiency across the eastern Greater Bay Area.
