Badong (Hubei), July 25, 2021

Construction workers celebrate the completion of the Badong Tunnel, the last 10,000-meter-long tunnel on the Zhengzhou-Wanzhou High-Speed Railway (photo taken on July 25).

On July 25, after 1,697 days of arduous efforts, the Badong Tunnel, a controlling project on the Zhengzhou-Wanzhou High-Speed Railway, was completed. It is the last 10,000-meter-long tunnel to be completed on the Zhengzhou-Wanzhou High-Speed Railway, marking major progress in the project's construction.

The tunnel was built by China Railway No. 5 Engineering Group Co., Ltd. and is located in Badong County, Hubei Province. It has a total length of 13,248 meters and includes an entrance and three adits, No. 1, No. 2 and No. 3. The tunnel is dominated by Class IV and V surrounding rock, and its geological conditions are extremely complex, combining adverse geology such as deformation and collapse, mud and water inrush, high temperature and weak surrounding rock. The tunnel passes through landslide bodies, faults, rock piles, coal seams and gypsum strata. Construction involves high risk, great difficulty and a tight schedule, making it a high-risk tunnel in weak surrounding rock.

China Railway No. 5 Engineering Group adopted information-based and intelligent management and introduced advanced intelligent supporting equipment such as fully computerized three-boom rock drilling jumbos, achieving mechanized operations across the entire process, including drilling and blasting excavation, initial support, invert filling, waterproofing and drainage, arch and wall lining, and lining maintenance. In addition, the mechanized large-section excavation method was used. During construction, advanced geological forecasting, advanced horizontal drilling, transient electromagnetic water detection ahead of the face and real-time monitoring with a fully automatic section detector were strengthened to achieve dynamic control of safety risks in tunnel operations. The project achieved a remarkable record of 121 meters of excavation and support, 130 meters of invert construction and 130 meters of secondary lining in a single month.

The Zhengzhou-Wanzhou High-Speed Railway is an important part of the "Eight Vertical and Eight Horizontal" high-speed railway network in China's medium- and long-term railway network plan. It runs from Zhengzhou in Henan in the north to Wanzhou in Chongqing in the south, with a total length of 818 kilometers and a designed speed of 350 kilometers per hour. The Hubei section is 286 kilometers long and passes through Xiangyang, Shennongjia, Yichang and Enshi before ending in Wanzhou, Chongqing. The railway is expected to be completed and opened to traffic in 2022.