Recently, a burst of cheers accompanied the rupture of a wall as, in the shaft at Quanyun Road Station on the southern extension of Shenyang Metro Line 2 near Taoxian Airport, a tunnel boring machine calmly broke through the last millimeter of earth, emerging exactly at the planned position.

According to reports, without affecting any surface activity, the shield machine began tunnel excavation from Quanyun Road Station on Metro Line 2 in early March this year, solving hundreds of problems large and small and completing the dual-line underground breakthrough of the Gaoqu section in one continuous effort.

The southern extension of Shenyang Metro Line 2 that broke through this time is 14.2 kilometers long and is a north-south trunk line of Line 2 laid along the city's "Golden Corridor." Once completed, the line will closely connect two first-class transportation hubs, Shenyang North Railway Station and Taoxian International Airport, achieving the goal of "air-rail intermodal transport." This is of great significance for improving Shenyang's comprehensive transportation system, driving industrial upgrading, expanding domestic demand and investment, and promoting the scientific and harmonious development of Shenyang's economy and society.

Shenyang is one of the first 10 pilot cities in China for underground utility tunnel construction. Five projects have been completed so far, among which the Nanyunhe section used a shield machine produced by Northern Heavy Industries.

The Nanyunhe section is 12.6 kilometers long and has a total of 7 shield shafts and 6 shield-driven sections. It is the country's first urban old-city underground utility tunnel constructed entirely using the shield method, passing through Nanhu Park, Lu Xun Park, Qingnian Park, Wanliutang Park, and Wanquan Park. It contains six types of pipelines: water supply, reclaimed water, natural gas, electricity, communications, and heating, and is equipped with a natural gas compartment, a heating plus communications compartment, a water compartment, and an electricity compartment. The project was rated as one of the "Top Ten Demonstration Projects of China's Urban Underground Utility Tunnel Engineering in 2018."