On October 9, as the massive cutterhead of the "Zhuangmei" shield machine broke through the soil, the Liucun Tunnel on the Nanning-Chongzuo Intercity Railway—Guangxi's first high-speed rail shield tunnel—officially achieved breakthrough.

The Liucun Tunnel is a key project for connecting the under-construction Nanchong Intercity Railway to the Nanning railway hub. With a total length of 5,725 meters, the tunnel is designed as a single-tube, double-track structure. Because the route passes through the urban area of Nanning and runs beneath 9 railway lines, 6 municipal roads, 1 metro line, 12 building clusters and 27 various types of underground pipelines, construction is highly difficult and safety risks are high, so it has been listed as a key control project for the entire line.

To ensure construction safety and reduce building demolition, after research by all parties and review by China State Railway Group, it was finally decided to adopt the shield method for construction, minimizing the impact on the urban environment.

As Guangxi's first under-construction high-speed rail tunnel built using the shield method, the Liucun Tunnel uses a 12.86-meter large-diameter slurry shield machine for excavation. The shield-driven section is 4,006 meters long, accounting for 70% of the tunnel's total length.

To ensure construction safety and quality, the construction unit formed a technical research team and, starting from multiple aspects such as excavation parameter control, automatic track surface monitoring, and settlement observation data monitoring, built a visual and information-based smart construction management platform that includes modules such as remote automatic monitoring and collaborative management, enabling safe and efficient construction. At the same time, the Liucun Tunnel project implemented 24-hour shift operations without interruption, advancing an average of 12 meters per day. After 20 months, it finally successfully completed underpass excavation in a complex environment and achieved "zero settlement."

After the tunnel breakthrough, the construction unit will accelerate the construction of auxiliary structures and ballastless track, striving to complete all construction tasks within 4 months and reach track-laying conditions in preparation for track laying.

The main line of the Nanchong Railway is 119.29 kilometers long, with a design speed of 250 kilometers per hour. As of now, the completion rates of the subgrade, bridge and tunnel projects along the entire Nanchong Intercity Railway all exceed 98%, more than half of the station building project has been completed, and the entire line has entered the two-way track-laying stage. It is expected to be completed and opened to traffic in 2022. By then, travel time from Nanning to Chongzuo will be shortened from 2 hours to 30 minutes, and it will take only 12 minutes from Nanning Railway Station to Nanning Wuxu International Airport, providing solid transportation infrastructure support for Guangxi's all-round integration into the "Belt and Road" and the New Western Land-Sea Corridor.