On August 24, as the shield machine's cutterhead slowly broke through the soil, the right line of the shield-driven section from Yinyue Guangchang (Music Square) Station to Meishan East Station on the Chengdu-Meishan (Chengmei) suburban railway, constructed by PowerChina Railway Construction Co., Ltd., was successfully holed through. With this, all 2 shield-driven sections in the Meishan segment of the Chengmei Line have been completed, marking a breakthrough in the project's construction.

As the "same-city main corridor" connecting Chengdu and Meishan, the Chengmei Line is a key link in building the transportation network of the Chengdu-Chongqing economic circle. The line's total shield-driven section is 19.45 kilometers long, of which the Meishan segment totals 9,074 meters, accounting for 46% of the whole line. PowerChina Railway Construction organized scientifically, applied precise measures, and took multiple steps to ensure safe and efficient tunnel holing-through.First, precise design to consolidate the foundation for safe tunneling.To ensure construction safety, through repeated preliminary verification, the design of the line's burial depth and gradient was optimized to actively avoid unfavorable geological areas such as liquefied sand layers, effectively controlling the risk of surface settlement. This strategy of "detouring around hazards" laid a solid foundation for subsequent smooth tunneling.Second, equipment upgrades to create intelligent construction tools.In accordance with geological requirements and the construction optimization plan, the shield construction of the Meishan segment of the Chengmei Line used 4 high-power shield machines with a diameter of 8.2 meters, and targeted technical upgrades were made based on formation characteristics, significantly reducing equipment wear. In response to problems such as "mud caking" and "blowouts" that easily occur during tunneling, the team optimized the cutterhead design and strengthened muck conditioning, greatly improving tunneling efficiency and stability.Third, technological support to solve the challenges of mixed strata.Facing technical difficulties such as settlement and segment flotation caused by complex strata, the project introduced multiple advanced technologies such as "single pipe, single pump" muck conditioning, middle-shield mud injection, and simultaneous two-component grouting, and strictly implemented the "gas-electric and wind-electric interlock" safety measures for gas tunnels, achieving intelligent monitoring throughout the process and successfully ensuring safe passage through high-risk sections. In addition, the entire line vigorously promoted green construction; through multi-stage screening and mud-water separation technology, the harmless treatment and resource utilization of shield muck were achieved, the water recycling rate was significantly improved, the concept of green construction was fully practiced, and the responsibility of a central state-owned enterprise was fully demonstrated.

PowerChina Railway Construction will continue to carry forward the project management philosophy of "quality first, always strive for the best," stay focused on the annual task targets, and with greater fighting spirit and a more solid work style, advance subsequent construction to high standards and ensure that the Chengmei Line achieves its goal of opening to traffic.