China News Service, Chongqing, October 14th (Zhang Xu) The Beijing-Kunming High-speed Railway Xikun Co., Ltd. announced on October 14th that on that day, the Sifangshan Tunnel, a key and difficult project of the Xi'an to Chongqing High-speed Railway (hereinafter referred to as the "west-Chongqing High-speed Railway") constructed by the China Railway 11th Bureau, was successfully completed, laying a solid foundation for the entire line to be completed and opened to traffic on schedule.
The Sifangshan Tunnel is located in Kaizhou District, Chongqing City, with a total length of 9,485 meters. The geological conditions are complex. It passes through landslides, goaf areas, old kiln water accumulation areas, harmful gas zones and karst water development areas. It has unfavorable geology such as high ground stress and side slope bedding, making construction organization and safety control difficult.
The picture shows the interior of the Sifangshan Tunnel of the west-Chongqing High-speed Railway. Photo by Zheng Yehui
In the construction of this tunnel, China Railway No. 11 Bureau implemented full-process mechanized construction and formed a "7+1+4" mechanized supporting matrix in the three major operating areas of the tunnel face, invert and second lining: the tunnel face was equipped with a three-arm rock drilling rig and multi-functional chargers. Seven types of equipment including trolleys are used. A 56-meter long-span mobile trestle is used for the inverted arch operation. Four types of equipment are introduced for the second lining operation, including intelligent lining trolleys and automatic laying and hanging trolleys for reinforced waterproof panels, realizing mechanized coordination of the entire process of excavation, support and lining.
According to Pu Kun, chief engineer of the 15th bid project of Xiyu High-speed Railway of China Railway 11th Bureau, during the construction process, the team innovated the "three-arm articulated steel arch overall mechanized installation" process, and the single erection cycle time was shortened from 3 hours to 2 hours, and the personnel investment was reduced by half; The developed automatic laying and hanging trolley for reinforced waterproof panels can complete the overall lifting and precise laying of 120 double-layer steel bars in a 12-meter lining circumference. It also has the functions of laying wide waterproof panels and automatic welding. The number of standard workers is reduced by 30%, and labor intensity is significantly reduced.
At present, China Railway No. 11 Bureau has formed 3 provincial and ministerial-level construction methods and more than 20 patents based on the construction of this tunnel, and participated in the preparation of the "Xi-Kunming High-speed Railway Tunnel Mechanization Innovation Practice and Transformation" and "Technical Regulations for Mechanized Design and Construction of the Full Process of Railway Tunnels."
The data picture shows the construction site of the Sifangshan Tunnel of the west-Chongqing High-speed Railway. Photo by Zheng Yehui
The West-Chongqing High-speed Railway is an important part of the Beijing-Kunming Channel and the Baotou (Yin)-Sea Channel in China's "Eight Vertical and Eight Horizontal" high-speed railway network. The Xi'an to Ankang section of the Xi'an-Chongqing High-speed Railway was put into operation on September 28. The construction of the Kangyu Section of the West-Chongqing High-speed Railway is advancing at full speed, with 67 tunnels already connected. The project as a whole has entered the critical stage of the remaining projects such as ballastless track construction, station building construction, and installation of four power projects.
After the West-Chongqing High-speed Railway is completed and opened to traffic, it will be interconnected with many trunk railways such as the Chengdu-Chongqing High-speed Railway, Zhengzhou-Chongqing High-speed Railway, and Chongqing-Kunming High-speed Railway, further improving the road network structure of high-speed railways in the central and western regions, and greatly facilitating the travel of people along the line. (over)
