Chongqing Rail Transit Line 7 has achieved a significant milestone: the left tunnel boring machine has successfully reached the receiving end in the section between Logistics Park North Station and Logistics Park South Station. This marks the completion of dual-tunnel excavation for this section, making it the first segment of Chongqing Rail Transit Line 7 to achieve dual-tunnel breakthrough. This progress represents a new phase in the construction of this important urban rail transit line connecting key city areas.
The left tunnel of the North-South section spans approximately 1,334 meters, with tunnel depth ranging from 13.9 to 35.2 meters. The tunnel features a circular cross-section design, with a maximum gradient of 20‰ and a minimum turning radius of 450 meters.
To overcome construction challenges including continuous small-radius curve excavation and tunneling underneath existing buildings, the project team established specialized technical groups to develop targeted construction plans. Using real-time tunnel boring machine guidance systems and monitoring systems, the team dynamically adjusted excavation parameters, enhanced settlement monitoring, and optimized grouting processes and pressure control. These measures effectively mitigated construction risks, ensured precise tunnel alignment and segment assembly quality, and achieved zero disruption to existing buildings, municipal roads, and underground pipelines along the route.

Upon completion, Rail Transit Line 7 will further enhance Chongqing’s public transportation network, improve travel conditions for residents along the route, and provide crucial transportation support for regional economic development.