On October 11, the "Chuxin" double-shield TBM on the left line of the section from Jiadingshan Station to Anshan Road Station in the south section of Qingdao Metro Line 8 broke through the rock and successfully reached the designated receiving adit. With this, the longest TBM section in Shandong Province achieved twin-tube completion three months ahead of schedule.

At the construction site of Anshan Road Station on Qingdao Metro Line 8, workers were busy with concrete construction. At the breakthrough site, the "Chuxin" double-shield TBM on the left line had broken through the rock. It is understood that the section from Jiadingshan Station to Anshan Road Station on Line 8 is 2,408 meters long in total, and two double-shield TBMs with a diameter of 7 meters were deployed, each equivalent to the height of two and a half stories and weighing 1,000 tonnes.

According to reports, the section from Jiadingshan Station to Anshan Road Station needed to pass beneath 15 buildings, 30 geological fault zones, and one petroleum depot, making it a first-level major risk source for the entire line. Any slight negligence could lead to dangers such as TBM jamming, tunnel face collapse, ground settlement, and damage to buildings. Because the original TBM launch site was surrounded by numerous buildings, all participating parties made a bold attempt by demolishing a nearby factory building to serve as the launch site. After repeated coordination among all parties, the site entry conditions were finally achieved. Since direct launching above the line was not possible, the TBM needed to be translated. To ensure safety and improve efficiency, all participating parties innovated and optimized the traditional "track-first, then push" translation and empty-pushing process, and jointly developed with a domestic advanced equipment manufacturer a "TBM hydraulic shifting device" and "supporting transfer trolley." It took only 27 days to complete the assembly and launching of a single TBM, saving more than 30 days compared with the traditional process.

In addition, in response to the project's characteristics, difficulties, and risk points, all participating parties pooled their wisdom, worked together, and stayed close to the front line. Through advanced technology and management methods, they compacted the responsibility system layer by layer and overcame difficulties one by one. Through the efforts of all parties, the fastest single-tube excavation speed in the section from Jiadingshan Station to Anshan Road Station reached 520.5 meters per month, setting a domestic record for TBM excavation under equivalent working conditions. Ultimately, the 2,408-meter excavation of the section from Jiadingshan Station to Anshan Road Station was completed in only 8 months, accumulating valuable experience for similar projects in Qingdao Metro.

Qingdao Metro Line 8 has a total length of 61.4 kilometers, of which the south section is 13.1 kilometers long. The section completed this time is from Jiadingshan Station to Anshan Road Station, and is the longest TBM section in Shandong Province to date." said Zhang Lei, owner representative of Qingdao Metro Line 8 Co., Ltd. The south section of Line 8 has 7 stations and 6 sections, including four mined stations and three open-cut stations. At present, all four mined stations have been completed, one open-cut station has been completed, and the other two are under accelerated construction.