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Technology for Tunnel Construction with Special Applications for Wanjiazhai Water Transfer Project
Published in Harald Wagner, Alfred Schulter, Tunnel Boring Machines, 2020
It is fairly clear that almost all projects which involve long tunnels for inter-basin transfer of water will require the use of the TBM. The use of the TBM basically gives a far better economic solution for tunnels greater than about 13.5 km, and construction quality can be assured, and speed of construction gives a much shorter implementation period. In addition safety of workers and better quality control can be achieved.
Rock excavation techniques
Published in Ömer Aydan, Rock Mechanics and Rock Engineering, 2019
A tunnel boring machine (TBM) is used to excavate tunnels, shafts and raise-bores with a circular cross section through various ground conditions. Tunnel diameters can range from 1 m to 17.6 meters to date (Figure 6.62). Tunnel boring machines are used as an alternative to drilling and blasting (D&B) methods in rock. The first successful application of the TBM was during the construction of the tunnels beneath Thames in 1825. TBMs have the advantages of limiting the disturbance to the surrounding ground and producing a smooth tunnel wall. This significantly reduces the cost of lining the tunnel. When surrounding rock is heavily fractured and sheared, the TBM may get stuck. Modern TBMs typically consist of the rotating cutting head, followed by a main bearing, a thrust system and trailing support mechanisms. The type of machine used depends on the particular geology of the project, the amount of groundwater present and other factors. TBMs can be shielded or open depending upon the ground condition. When the face is unstable or the groundwater condition is bad, earth-pressure balanced (EBP)–type TBMs are used.
Tunnelling Operations
Published in S. Ponnuswamy, D. Johnson Victor, Transportation Tunnels, 2017
S. Ponnuswamy, D. Johnson Victor
This is an extension of the shield tunnelling technology. A TBM (Tunnel Boring Machine) is used, which can work on full face of the tunnel at one time, by varying the type of tools to suit the type of soil, slush to rock. The TBM is designed to support the surrounding soil after excavation, till the lining is provided behind. Generally CI or precast segmental linings are provided.
Distinct element method analysis of jointed rock fragmentation induced by TBM cutting
Published in European Journal of Environmental and Civil Engineering, 2018
Mingjing Jiang, Youbin Liao, Huaning Wang, Ya Sun
With the increase ability of cutter of shield machines, shield tunnelling can be applied to tunnel construction in various strata (Gong, Zhao, & Jiao, 2005; Shen, Wu, Cui, & Yin, 2014; Wu, Shen, Liao, & Yin, 2015) from very soft Quaternary deposit, weak rock strata or even hard rock. Both shield machine and TBM can be conducted under confined aquifer (Shen & Xu, 2011; Shen, Ma, Xu, & Yin, 2013; Shen et al., 2015; Wu, Shen, & Yuan, 2016; Xu, Shen, Ren, & Wu, 2016; Yin, Karstunen, Chang, Koskinen, & Lojander, 2011; Yin, Xu, & Hicher, 2013; Yin, Zhao, & Hicher, 2014; Yin, Yin, & Huang, 2015). With the development in the West Regions in China, a growing number of tunnels are launched in full swing in hydraulic and hydro-power projects. Tunnel boring machine (TBM) is more widely employed in tunnel excavation for its features of high efficiency, safety and environmental protection (Cui et al., 2016; Shen et al., 2017a).