By rosebell
In order to advancing China’s South-to-North Water Diversion Project, the Railway Construction Heavy Industry Corporation Ltd (CRCHI) has rolled off an open-type rock TBM.
As the largest of its kind in China, this machine has 11.93m-diameter.
Diverting the Yangtze River to supplement the Han River, the central section of the South-to-North Water Diversion Project will be the location of using TBM Jianghan Neolithic, whereas it also is going to excavate the largest and longest soft rock deformation section of the project.
With almost 175m length and around 3,000 tons weight, this TBM has a designed minimum radius of 800m and adapts to a maximum slope of 10%. With an immersive intelligent excavation system, it has real-time visualisation of the geology in front of the TBM, precise autonomous control of excavation routes, automatic posture correction, and automatic excavation step change. Additionally, construction of the 3rd Section traffic tunnel and main tunnel and digging a total distance of 16.35km will be up to TBM Jianghan Neolithic.
As one of China’s water diversion undertakings, this project’s geological conditions are complex, with a large overburden, long distance, large tunnel diameter, multiple faults, soft rocks, high in situ stress, and high water pressure and so the TBM is due to encounter many construction challenges such as high-strength rock bursts, mud inrushes, large fractures, soft rock deformation, and harmful gases.
With the aim of overcoming these conditions, the CRCHI R&D team designed the TBM with a small spaced, large cutterhead, double support of steel arch and steel segments, main drive anti-surge door, and configured a double-speed ratio high-torque reducer, shield lubrication and anti-friction system, with shield strain gauge detection and early warning device, while the TBM also features a steel arch transport and feed system, and remote-control material removal.
Considering that creating the main framework and artery of the national water network is the intention of this plan, diverting the Yangtze River to supplement the Han River Project is a crucial step in this project. Following this is done, the South-to-North Water Diversion Project and the Three Gorges Dam Project will be connected, linking the Yangtze River Basin, the Han River Basin, and the Beijing-Tianjin-North China region to form a new water supply network and improve water resources for these regions.
