Recently, as the shield machine's cutterhead broke through the wall, the left-line shield of the Guanziqiao Station to Jiangdongmen Station section (hereinafter referred to as the "Guanjiang Section") of Phase I of Line 9 was successfully received, marking the smooth completion of the double-line tunnel of the Guanziqiao Station to Jiangdongmen Station section.

The entire Guanjiang Section is located in the Yangtze River floodplain strata, with the section's hydrogeology consisting of silty clay layers of mucky soil, where the soil mass has poor self-stability. Jiangdongmen Station and Guanziqiao Station are located on Jiangdong Expressway, a main arterial road in Nanjing, surrounded by numerous residential communities and shops and a large number of utility lines; the shield machine successively crossed multiple utility lines and buildings (groups). In the face of construction difficulties such as the complex surrounding environment and the high difficulty of shield tunneling, Nanjing Metro organized expert demonstrations and formulated special plans to fully overcome the technical challenges. Both lines of the Guanjiang Section adopted the "cup-type" horizontal freezing reinforcement method for launching and receiving; the overall effect of horizontal freezing reinforcement was good, and the steel sleeve was eliminated at the receiving end, reducing procedures and shortening the construction period, ultimately achieving the safe launching and receiving of the shield, and also laying a solid foundation for subsequent track laying and installation work.

Phase I of Nanjing Metro Line 9 starts at Hongshan New Town Station and ends at Jiangsu Grand Theatre · Constitution Square Station, with a total length of 19.684 km, entirely underground, with 16 stations in total, including 9 transfer stations. The line passes through Xuanwu District, Gulou District, and Jianye District; after completion and operation, it will be an important local line connecting the central Hexi area, Xiaguan, and Xinzhuang areas within Nanjing's main urban area.