Recently, as the "Municipal Pioneer No. 1" shield machine slowly entered the shield receiving shaft, the left line of the Zhongjian section of Phase I of the Changchun Rail Transit Line 9 project achieved smooth breakthrough, laying a solid foundation for the subsequent full-line breakthrough.

The geological conditions in the Zhongjian section are complex. The tunnel passes through a variety of special strata, including strongly weathered conglomerate, completely weathered conglomerate, and silty clay. The groundwater system is abundant, and the breakthrough construction is difficult and high-risk.

Since the start of construction in the shield section, the Changchun Metro Project Headquarters has coordinated the efforts of all parties, adhered to tackling both scientific epidemic prevention and work resumption, and the Fifth Work Area Project Department has carefully formulated construction plans. They overcame many difficulties, including harsh winter construction conditions, complex geological conditions, water intake difficulties, muck transport, and the impact of the epidemic. Under the premise of ensuring construction quality and safety, they steadily advanced the construction process and ultimately achieved the smooth breakthrough of the left line of the Zhongjian section, firing the "first shot" for the future full-line breakthrough.

After Changchun Rail Transit Line 9 connects with the future eastern extension of Changchun Rail Transit Line 2, it will become an important corridor linking the airport with the main urban area, effectively connecting Changchun's urban districts, the Lianhuashan Ecological Tourism Resort, Changchun New Area, and Jiutai District. It is of great significance for promoting the development of Changchun's eastern urban area and alleviating passenger flow pressure.