Physical Model Test on the Behavior of Large Slurry Shield-Driving Tunnel in Soft Clay

doi:10.1007/s12204-013-1451-9

Abstract

Abstract: As the dimension of the slurry shield is greatly increasing, more and more attention is paid to the face stability of slurry shield-driven tunnel in recently years. A reduced-scale slurry shield model test is carried out based on the background of Qianjiang River Tunnel and Shanghai Yangtze River Tunnel. The results of the model test are presented in this paper with particular emphasis on the slurry shield driving parameters and the critical slurry pressure of the excavating face. It is shown that the behavior of large slurry shield-driving induced by the cutting face is mostly decided by the fluctuation of the slurry pressure in the chamber, and a smaller slurry pressure fluctuation range is presented according to the results of the physical model test. Especially, it is more difficult to control the machine in sandy silt than that in soft clay and muddy clay. The chamber pressure will fluctuate greatly when excavating in high permeability ground, and the gradient of accumulation of the flux difference could be used to evaluate the face balance of the slurry shield excavation.

Key words: slurry pressure balanced method| physical model test| slurry pressure| tunnel

摘要： As the dimension of the slurry shield is greatly increasing, more and more attention is paid to the face stability of slurry shield-driven tunnel in recently years. A reduced-scale slurry shield model test is carried out based on the background of Qianjiang River Tunnel and Shanghai Yangtze River Tunnel. The results of the model test are presented in this paper with particular emphasis on the slurry shield driving parameters and the critical slurry pressure of the excavating face. It is shown that the behavior of large slurry shield-driving induced by the cutting face is mostly decided by the fluctuation of the slurry pressure in the chamber, and a smaller slurry pressure fluctuation range is presented according to the results of the physical model test. Especially, it is more difficult to control the machine in sandy silt than that in soft clay and muddy clay. The chamber pressure will fluctuate greatly when excavating in high permeability ground, and the gradient of accumulation of the flux difference could be used to evaluate the face balance of the slurry shield excavation.

关键词: slurry pressure balanced method| physical model test| slurry pressure| tunnel

CLC Number:

U 455.43

HU Xin-yu1* (胡欣雨), ZHANG Zi-xin2 (张子新). Physical Model Test on the Behavior of Large Slurry Shield-Driving Tunnel in Soft Clay[J]. Journal of shanghai Jiaotong University (Science), 2013, 18(6): 693-698.

References

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