On October 26, 2020, the Tongjing Road Tunnel in Suzhou City, Jiangsu Province began shield tunneling. The excavation diameter of the shield machine was 13.67 meters, which is China's first large-diameter shield tunnel underneath an operating high-speed railway.

The north extension project of Tongjing Road has a total length of 2066.703 meters. It passes through Shanghai-Nanjing Expressway, Shanghai-Nanjing Intercity Railway, Shanghai-Nanjing Railway and Beihuan Expressway in the form of a shield tunnel. The tunnel is designed as a two-hole six-lane, one-way long 490 meters. Among them, the Shanghai-Nanjing intercity high-speed rail, which the shield tunnel passes under twice, has a design speed of 350 kilometers per hour. It is one of the busiest high-speed rail lines in China. The minimum travel interval is 3 minutes. The settlement of the high-speed rail line during the construction period must be controlled within 1 mm. precedent. Editor/Xia Changwang