By Ashley Karen
China Railway Group, the Chinese contractor, has launched two ‘super-large’ diameter TBMs (tunnel boring machines) for high-speed rail tunnel’ construction.
The firm declared that the ‘Yongan’ tunnel boring machine was China’s first super-large diameter dual-mode shield machine, with an excavation diameter of 14.29 meters, a total length of 117 meters and a weight of nearly 4,250 tones.
The TBM is equipped with eight main beam panel cutter heads, while the cutters feature improved impact and wear resistance.
The machines, together developed by China Railway Tunnel Group and China Railway Engineering Equipment Group, will bore a total of 3.96km for the Guifengshan Tunnel on the Jiangji section of the Zhuzhao high-speed railway.
The railway line in Guangdong province will operate for a total length of 98.6km, with tails driving at a speed of 350 km/h. The tunnel itself will be 15km long.
While ‘Yongan’ was launched in Shunde, another dual-mode shield tunnel boring machine called ‘Huatong Fenjin’ was launched from Zhongshan.
