On July 23, as the cutterhead of the "Liuju No. 4" shield machine slowly pushed open the tunnel face at the receiving end of the left line, the shield tunneling of the Dongshuniu Station–Sandaocun West Station section in Work Zone 1 of the Changchun Rail Transit Line 2 East Extension Project undertaken by China State Construction Engineering Corporation (CSCEC) was successfully completed, achieving the milestone target 7 days ahead of schedule and marking the full tunnel breakthrough of the entire Changchun Rail Transit Line 2 East Extension Project.

The shield-tunneled Dongshuniu Station–Sandaocun West Station section completed this time has a total length of 2,000.038 meters and is the longest shield-tunneled section among the third-phase construction projects of Changchun Rail Transit. The shield machine passed beneath the East Jilin Avenue main road, the Beijing–Harbin Expressway, and steel-frame bridges, with complex and intricate pipelines above, including municipal rainwater pipelines, water transmission and distribution pipelines, and gas pipelines. The geological conditions are complex and variable, groundwater is abundant, and attitude control of the shield machine was difficult. The ground traffic volume at the shield receiving end is heavy, with many heavy-duty vehicles, posing significant safety hazards to the receiving work. In particular, the receiving end of the left line is located directly beneath the Changshi Highway, where the overburden is shallow and the soil is mostly mucky soil and silty clay; the low soil strength made it prone to considerable collapse risk.

Faced with numerous uncertain factors affecting construction, the project team did not wait or rely on others, but united as one and overcame difficulties. They formulated strict safety management systems and emergency response plans, and adopted targeted measures for different strata; repeatedly invited experts to the site for analysis, judgment, and guidance; persisted in daily on-site inspections with 24-hour rotating shifts; strengthened surface and in-tunnel monitoring at fixed times and locations; enhanced the quality of secondary grouting and strictly controlled segment assembly quality; and formulated scientific and rigorous shield receiving and traffic diversion plans, ultimately successfully completing the shield receiving work for the section and achieving the milestone target of full tunnel breakthrough.

Next, the CSCEC Changchun Rail Transit Line 2 East Extension Project will continue to implement refined management requirements, closely follow high-quality development requirements and project construction goals, continuously strengthen safety and quality control, and strive to achieve the smooth opening of Changchun Rail Transit Line 2 as early as possible, contributing greater strength to expanding happy living space for Changchun.

It is reported that the Changchun Rail Transit Line 2 East Extension Project is a connecting line between Line 2 and Line 9 (Airport Line). The line starts from Dongfang Square Station of Line 2, with a total length of 10.6 km and 6 stations, all underground. Among them, Zhaojia Gangdong Station is the transfer station between Line 2 and Line 9 (Airport Line), and a Lianhuashan parking lot is set up at the end of the line. After the project is completed, it will realize interconnection between Line 2 and Line 9, providing direct access toward Longjia Airport, making the urban spatial layout more reasonable and public travel more convenient.