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Completion Ceremony for The Baicheng Tunnel of Menghua Railway

Constructing mountain tunnel in loess stratum usually employs advance support, sequential excavation method (SEM) and double lining. Such method is lack of safety and slow. Therefore, CREC has developed the large horseshoe-shaped EPB-TBM with multiple cutterheads for the mountain tunnel project in loess. Compared with conventional SEM, the proposed method in the project is safe and fast. It could also guarantee the quality of construction and the working environment. Compared with single circular cutterhead EPB-TBM, newly developed horseshoe shape EPB-TBM with multiple cutterheads could reduce manufacture cost of the TBM, increase utilization ratio of the section, and reduce the quantity of excavation and construction material. The section is 10.95 m high and 11.9 m wide. The construction method is successfully used in the Baicheng tunnel of Menghua Railway, which is 3345m long and lies in the sandy new loess. The range of the overburden is from 7 m to 81 m.