On September 3, the first-piece acceptance of the diaphragm wall works for the Heping Convention and Exhibition Center Station of the Hangzhou Metro Project Bid 15-11 was successfully passed, laying a solid foundation for the next stage of construction. The acceptance was organized, supervised and guided by the Hangzhou Municipal Quality Supervision Station and the Third Construction Branch of Hangzhou Metro Group, and was attended by all project participants.

Section SG15-11 of Phase I of Line 15 comprises two stations and two running tunnels, namely Datieguan Station, Heping Convention and Exhibition Center Station, the running tunnel between Heping Convention and Exhibition Center Station and Santang Station, and the running tunnel between Datieguan Station and Heping Convention and Exhibition Center Station. Datieguan Station is the only four-level underground station on Hangzhou Metro Line 15 built using the covered top-down construction method, with the deepest point of the end shaft reaching 36.26 m.

The retaining structure of Heping Convention and Exhibition Center Station adopts 800 mm wide diaphragm walls, with a maximum depth of 40 m. The geology from top to bottom consists of gravelly fill, mucky clay, silty clay and sandy silty clay. The station construction area is located in the main urban area of Hangzhou, surrounded by densely packed high-rise buildings and numerous residents, making the construction environment extremely complex and posing greater challenges to the organization of diaphragm wall construction. Through proactive communication and detailed planning in the early stage, the project team successively overcame difficulties such as muck disposal, concrete supply and nighttime construction, laying a solid foundation for the smooth implementation of the first-piece works of the diaphragm wall. This acceptance work was carried out comprehensively in two parts: the quality of the first-piece works and the internal documentation.

The acceptance team went deep into the construction frontline and carefully inspected the quality of key construction processes such as trench excavation, reinforcement cage welding and concrete pouring. At the acceptance meeting, the team listened to a report on the construction of the diaphragm wall and, in strict accordance with the design requirements of the specifications, the provisions on first-piece acceptance management of engineering quality and other relevant industry standards, reviewed and accepted the first-piece documentation of the diaphragm wall. The completed quality of the first diaphragm wall piece was fully affirmed by the acceptance team, and all parties unanimously agreed to pass the acceptance.

The passing of the first-piece acceptance of the diaphragm wall has set a guiding example and laid a solid foundation for subsequent diaphragm wall construction. The project will always adhere to standardized construction, rigorously improve engineering construction quality, strengthen communication and coordination, and enhance the project team's ability to tackle difficulties, ensuring that the diaphragm wall construction of the Heping Convention and Exhibition Center retaining structure is completed with high quality and efficiency.

As a north-south trunk line, Phase I of Hangzhou Metro Line 15 starts at Yatai Road Station in Xiaoshan District and ends at Chongxian Station in Linping District. The line connects core areas such as Qianjiang New City and Qianjiang Century City, links southward to the old city of Xiaoshan, and radiates northward to Chongxian in Linping.

Phase I of Line 15 has a total length of 41.02 km, all of which is underground, with 30 stations in total, including 15 transfer stations. It includes the Shushan South Vehicle Base and the Chongxian Parking Lot. The design speed target is 80 km/h, and the trains adopt Type Ah vehicles, with 6-car formations in the initial, near-term and long-term stages.