Recently, the No. 20315 shield machine, independently developed and manufactured by CCCC Tianhe, successfully completed tunneling for the left line of the Airport Station–Jiwen Ventilation Shaft section of Section 3 of the Fuzhou Binhai Express Line, marking the successful conclusion of the tunneling tasks for the 11 8-meter-class shield machines provided by our company for the Fuzhou Binhai Express Line.

The equipment that completed this breakthrough is an earth pressure balance shield machine, with a cutterhead diameter of 8.58 m, an overall length of 118 m, and an opening ratio of 33%. The section has a total length of 2,954.899 m. This shield machine was launched from the intermediate ventilation shaft on December 26, 2021, and tunneled toward the airport. Over 894 days and nights, it advanced a total of 1,641 rings and safely and successfully completed the construction tunneling task.

This section is one of the shield-tunneled sections with the most complex geological conditions along the entire Fuzhou Binhai Express Line. It passes through multiple stretches of full-face hard rock, upper-soft/lower-hard strata, and boulder clusters, where the mechanical properties differ extremely sharply. Adverse strata account for as much as 42%, and the highest rock strength reaches 205.8 MPa, generally ranging between 120 and 170 MPa. Over a long distance, it passes beneath major risk sources such as ancestral halls, the airport expressway, and the airport HE steel trestle.