On April 12, the reporter learned from Chongqing Rail Group that the North Extension Project of Chongqing Rail Transit Line 5 has made new progress: the main structures of two cut-and-cover stations, Ganyue Avenue Station and Chunxuan Avenue Station, were successfully capped simultaneously, providing favorable conditions for the subsequent smooth TBM section breakthrough and the on-schedule track laying and opening of the entire line, and marking that the project has entered the countdown sprint stage for track laying.

The North Extension Project of Chongqing Rail Transit Line 5 mainly spans Yubei and Liangjiang New Area. Ganyue Avenue Station is located at the intersection of Qiucheng Avenue and Ganyue Avenue, arranged north-south along Qiucheng Avenue. The station has an outer total length of 212.6 m and a width of 21.26 m, is constructed by the cut-and-cover method, and is equipped with 2 ventilation groups and a total of 4 entrances and exits. Chunxuan Avenue Station is an underground two-story, double-column cut-and-cover island-platform station. The station has a total length of 220 m, a total width of 23 m, and a total building area of 17,200 m2, equivalent to the size of 2.5 football fields. The station has a total of 4 entrances and exits, 1 barrier-free elevator at Entrance/Exit 2, 3 safety exits, and 2 ventilation groups (8 ventilation shafts). As the launching station for TBM and track laying of the North Extension Project of Line 5, it faces enormous pressure in construction organization, technical quality, resource allocation, and other aspects.

To ensure successful capping, the North Extension Project of Line 5 established an innovation studio as soon as the project started, continuously exploring methods and innovating technologies, and adopting sleeve valve pipe grouting technology to solve on-site problems. At present, project approvals have been completed for "Research on Key Technologies for Shield Construction in High-Water-Level Backfill Areas," "Research on Key Technologies for Construction of Extra-Large Cross-Section Stations Crossing Recently Backfilled Areas in Urban Rail Transit Projects," and "Research on Key Technologies for Muck Transport by Large-Longitudinal-Slope Horizontal Continuous Belt Conveyors." These have successively solved major construction difficulties such as TBM underpassing deep backfill areas and excavation of extra-large cross-section mined stations, overcoming numerous difficulties including complex and diverse engineering technologies, tight schedules, and great coordination challenges.

The two stations achieved capping of their main structures on schedule, providing prerequisites for subsequent above-ground structure construction and laying a solid foundation for the smooth tunnel breakthrough of the North Extension Project of Chongqing Rail Transit Line 5 by the end of the year.

It is reported that the North Extension Project of Chongqing Rail Transit Line 5 has a total length of 8.64 km. The line starts from Yuanbo Center Station of Phase I of Line 5 and ends at Yuegang North Road Station, with 7 stations and 1 Shizishan parking lot. Once completed, it will form a north-south backbone corridor together with Phase I of Line 5 connecting Dadukou District, Jiulongpo District, Shapingba District, Yuzhong District, Jiangbei District, and Yubei District, and is of great significance for alleviating the north-south passenger flow pressure on Chongqing's rail network and optimizing urban living and transportation travel.