Good news has arrived from the construction site of Section 17, Phase II of Beijing Subway Line 10, managed by Beijing Zhuzong Municipal Engineering Company—the first tunnel segment for the entire second phase of Line 10 has been successfully completed. As the Tiantun No. 7 tunnel boring machine (TBM) began operation, its cutterhead broke through the soil and gradually entered the pre-installed portal ring, seemingly smiling with joy as it marked this significant milestone. This breakthrough also signifies the smooth completion of the right-line tunnel section between Huoqiying Station and the line's terminus in this particular section. The right-line tunnel section in this segment measures 940.187 meters in length, while the left-line stretches 963.289 meters, totaling 1,903.476 meters overall. The TBM was launched on February 22, 2010, from the right-line starting point near Bagou Village. During its journey, it passed beneath several critical infrastructure elements, including the northbound track of Landing Factory North Road, the Kunyu River, and the southbound track of Landing Factory North Road. Additionally, it narrowly avoided crossing under the 1st to 2nd-floor structures of the Haidian Management Office of the Transportation Bureau, as well as the west-side bridge piers of the Wanquan River Interchange overpass—each posing unique challenges. Throughout the process, the TBM navigated through a complex web of underground utilities, including 41 distinct pipelines such as telecommunications cables, power lines, water supply and drainage systems, and gas pipes. Notably, among these were five major rainwater and sewage pipelines, each exceeding 1 meter in diameter.

　　The tunnel boring machine for this section was launched on a curved track with a 300-meter turning radius. Despite the challenging constraints of a confined construction site—specifically, the difficulty of positioning equipment in the narrow space between the two closely spaced, nearly 900mm-separated tunnels of the underground reverse excavation—the project team from Zhuzong Municipal Company’s No. 17 Section of Beijing Subway Line 10 Phase II successfully overcame these obstacles. As a result, they opted to deploy all ancillary equipment separately within the reverse tunnel’s curved configuration during the launch process. This innovative curved, split-launch method using a tunnel boring machine is being applied for the first time on the Beijing subway system.