CREG is delighted to announce that by 8 o’clock AM on March 25th, its U-shape TBM Menghua Hao has accomplished a monthly advance of 308.8m (from 8 o’clock AM on February 25th to 8 o’clock AM on March 25th).
Menghua Hao serves the single-bore double-track Baicheng tunnel (one tunnel with two tracks) whose maximum overburden is 81m. The project is scheduled to end in 37 months. Over the past few months, the U-shape TBM has crossed under Baotou-Maoming Highway and encountered sections where geological change is both large and unexpected. To address the problems with the muck transportation due to severe winter weather, CREG staff at the jobsite worked hard on ice clearance in advance and the routine maintenance of the U-shape TBM. Other measures like technical proposal revision and keeping eyes on monitoring the machine were also taken. Thanks to that, the advance of the tunnel was very good and the best daily advance was 10 rings. Up to now, the machine has driven 934.4m, successfully keeping the entire project on schedule.
Distinct Advantages of U-Shape TBM
The geology found in the area includes sand soil and neo loess. The conventional mining method costs a lot as it requires auxiliary methods and high-strength support. On the contrary, it is more cost-effective to work with TBM for only precast segment is needed.
Compared to drilling and blast method, which requires plenty of manpower and material resources and slow progress, TBM triples the efficiency while saving cost.
U-shape TBM overcomes disadvantages of enlarged excavation area, poor load-bearing capacity and additional supporting components as opposed to double parallel or triple circular shield machine.