Recently, with the successful pouring of the final batch of concrete for the foundation pit in Zone 2, the main structure of Sanlin South Station on Section 6 of the Shanghai Municipal Railway Airport Link Line—invested in and constructed by Shanghai Shentie and built by Shanghai Construction Group—has been successfully topped out, marking the station's full entry into the construction phase of ancillary structures. This is the largest station on the Airport Link Line and one of the largest station projects currently under construction in Shanghai.

▲ Rendering of Sanlin South Station

Sanlin South Station is located on the southwest side of the intersection of the S20 Outer Ring Expressway and Puxing Highway in Pudong New Area, running east-west along the S20 Outer Ring Expressway. It is an underground four-level dual-island four-track station with 12 entrances and exits and is designed to allow transfer with the under-construction Line 19. The station is approximately 667.5 meters long in total, with a total floor area of 90,474 square meters.

The standard section of the foundation pit at Sanlin South Station is excavated to a depth of approximately 36.33 to 37.30 meters, with 7 levels of concrete bracing; the west end shaft is excavated to a depth of 41.32 meters and the east end shaft to a depth of 42.61 meters, both with 8 levels of concrete bracing. The excavated earthwork volume is 850,000 cubic meters.

Among these, the foundation pits in Zones 3 and 1 completed structural topping-out on April 20 and May 23, 2023, respectively, while the foundation pit in Zone 2 is currently undergoing removal of the bracing frames, removal of the first level of bracing, and secondary structural works.

To strictly control the deformation risk during foundation pit excavation, the project team, at the fifth level of bracing at a depth of 24 meters inside the pit, effectively reduced the foundation pit deformation coefficient by using a self-developed concrete bracing servo system. In addition, during foundation pit dewatering, an intelligent management platform for suspended-curtain dewatering was adopted; through on-site automated collection of water level and water volume and the monitoring system server, it provides convenient and accurate information for supervising the dewatering works and effectively closes regulatory loopholes.

Through advance organization and overall coordination, Shanghai Shentie, during the backfilling and construction of the main structure in Zone 2, communicated fully with the track-laying and decoration and fit-out units, prompting the project team to optimize its own processes and techniques and increase staffing and equipment, and handed over the relevant construction work faces in a timely manner, effectively ensuring the progress of the backfilling and construction.

The Airport Link Line has a total length of 68.6 kilometers, passing through three administrative districts—Minhang, Xuhui, and Pudong New Area—with 9 stations across the entire line. Trains can reach a maximum operating speed of 160 kilometers per hour. Once the project is completed, the travel time between the two major comprehensive transportation hubs of Hongqiao and Pudong can be controlled at around 40 minutes, with transfers to multiple existing and under-construction rail transit lines, facilitating travel for residents and passengers along the line. At the same time, it will further enhance the radiating role of the Pudong and Hongqiao comprehensive transportation hubs in the Yangtze River Delta region, serve the Yangtze River Delta city cluster, and provide strong support for elevating Shanghai's global city level and core competitiveness and for implementing the national strategy of integrated development of the Yangtze River Delta.