On August 14, 2026, at the construction site of Phase I of Shenzhen Metro Line 22, the shield tunnel section on the right line from Luhu Station to Songxuan Station was successfully completed. With the final segment assembled in place, all four shield tunnels in the two sections managed by CR1G have been connected, making this work area the first to complete the main line shield construction on the entire line. The geological conditions at the construction site are complex and intricate, with hard rock layers and fractured fault zones intertwined and overlaid. The builders are facing multiple risks and challenges, steadily advancing the excavation operation.

Geological breakthrough

The project construction is adjacent to the Shipi Mountain in Mati Mountain, with diverse rock types and large fluctuations in rock surfaces. Some slightly weathered granite has a uniaxial compressive strength of 180 megapascals, which can easily cause damage to shield tunneling tools. The tunnel also needs to pass through fractured rock masses and fault zones with abundant groundwater, posing a constant threat to excavation safety due to water and sand influx and collapse hazards.

The project establishes a three in one shield tunneling management system, relying on 94 survey boreholes and 32 supplementary survey boreholes to identify 14 special geological risk points and accurately match shield tunneling equipment. With the help of HSP advanced geological exploration and surface ground penetrating radar scanning to predict risks, the implementation of soil pressure balance and air pressure assisted excavation mode, combined with grouting to stabilize the formation. During the entire construction process, all building settlements are within a safe range, achieving zero damage, zero penetration, zero collapse, and zero accidents.

Adhere to the bottom line of construction

The project follows the management guidelines for shield tunneling in the Shenzhen Metro Phase V project and implements the 1211 high-quality construction system, implementing five control measures to control surface settlement and pipe segment ellipticity deviation. Implement the three certificates and one trial acceptance mechanism for materials, and build a solid foundation for engineering quality from the source. The party branch is rooted in the front line of construction, relying on the party building and safety mode to sink management forces to the site. The team remained steadfast throughout the entire process, delivering construction results with zero defects and accidents, fully demonstrating the excellent strength of shield tunneling construction in complex geological formations. Keywords: Shenzhen Metro Line 22, Shield Tunnel Connection

After the first phase of Line 22 is put into operation, it takes 45 minutes from Futian to reach Guanlan, and 60 minutes to radiate to the Linshen area, connecting the Shenzhen Hong Kong Science and Technology Innovation Cooperation Zone Banxuegang Science and Technology City, relieving the traffic pressure at Meilin Pass, and adding momentum to the Shenzhen Central Expressway network.Editor/Min Jing