Recently, amid a rumbling roar, the cutterhead of the shield machine slowly broke through the wall, completing the shield tunnel between the Government Affairs Center Station and the Government Affairs Center East Station on Metro Line 22 (Pinggu Line), marking that the first shield-driven section of the Pinggu Line project has achieved two-way breakthrough.

The left line of the shield-driven section between Government Affairs Center Station and Government Affairs Center East Station of Bid Section 12 of the Pinggu Line was completed in June this year. The right line completed this time started excavation from Government Affairs Center Station, with a length of 625 meters, passing along Zhaoshan Avenue, Jingxing Road, Qingfeng Road, Hanying West Road and other locations eastward to Government Affairs Center East Station.

The project is located in the administrative office area of the sub-center. During excavation, unfavorable factors included numerous underground pipelines, dense surface buildings, loose geology and a high groundwater level. To ensure the shield construction passed safely through the above-ground building clusters and underground pipeline clusters, the project construction team investigated the possible risks along the section, compiling data from the structural forms and pile foundation types of buildings along the route to the dimensions of pipelines, and adjusted the excavation method based on the data. While taking into account the impact of man-made structures, the construction team also strictly calculated the amount of muck generated by excavation to ensure earth pressure balance and prevent possible groundwater inrush and surface settlement during shield driving.

As Beijing's first intelligent shield driving demonstration project for rail transit, the "Jishi No. 1" shield machine undertaking this excavation task adopted research and application of intelligent technologies such as autonomous shield driving. The shield attitude control system collects shield attitude and axis status in real time, and through artificial intelligence algorithms automatically controls the advance pressure of each zone, realizing functions such as surface driving of the shield, automatic pressure maintenance, automatic deviation correction, and real-time remote monitoring and warning.

The two-way breakthrough of this project is a landmark step in the construction of the Pinggu Line. Thereafter, the project team will continue to carry out construction of the cross passage and the main structure of the No. 1 air duct and Exit A of the auxiliary structures of Government Affairs Center East Station. Next, the project will fully implement all work with more rigorous measures and a more energetic spirit to ensure the project is completed on schedule.