On April 22, as the massive cutterhead of the "Tiejun No. 4" composite TBM broke through the wall, the right line of the TBM section from Jinshansi Station to Huanlegu Station (hereinafter referred to as the "Jinhuan section") on Phase II of Chongqing Rail Transit Line 15 was completed. Together with the previously completed left line, this marks the achievement of dual-line breakthrough in the section, laying a solid foundation for realizing the milestone goal of "full-line tunnel breakthrough."

A relevant person in charge of Chongqing City Transportation Development & Investment Railway Group introduced that the right line of the Jinhuan section is about 1,835 meters long, and the section has two horizontal curve segments in total, with the line longitudinal slope being a "V"-shaped slope section. The section is water-rich, with a long line, large gradient, complex geological conditions, high safety risks, and great difficulty in construction organization.

In response, the Phase II general contracting department of Chongqing Rail Transit Line 15 of China Railway Construction Corporation adopted a series of safeguard measures, continuously strengthening control over shield construction safety, quality, progress, risks, and other aspects. Using "Internet + BIM" technology, and relying on the "three-level linkage" smart monitoring system and equipment operation monitoring system, it conducted all-round, real-time monitoring of the site with no blind spots, dynamically adjusted tunneling parameters during the process, accurately controlled the tunneling speed, and ensured the smooth progress of TBM shield construction in the section.

At present, the construction management section of Phase II of Line 15 has completed the construction tasks of three TBM sections, and the left line of the last section, from Huanlegu Station to Jiuquhe East Station, also started smoothly on April 12.

Chongqing City Transportation Development & Investment Group stated that Chongqing Rail Transit Line 15 is the first urban rail express line in Chongqing's central urban area. After completion and opening to traffic, it will further accelerate the development of Chongqing's western trough valley, improve the structure and hierarchy of the rail transit network, and further facilitate citizens' travel.