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A numerical study on the waterproofing effect of Fan Grouting under tunnel excavation

터널 굴착 중 Fan Grouting의 차수 효과에 관한 수치해석적 연구

  • Received : 2019.01.08
  • Accepted : 2019.02.01
  • Published : 2019.03.31

Abstract

Ground water generated under tunnel excavation has a major impact on tunnel construction and stability. Thus, effective waterproof grouting is needed to reduce the inflow of groundwater. Most tunnel designs are applying the Pre Grouting. However there are no propriety analysis for grouting material and waterproof effect. In this study, numerical analysis was performed in order to investigate the effect of waterproof with decrease of coefficient of permeability of the grouting area based on the case of grouting construction.

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Fig. 1. Pre Grouting

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Fig. 3. Photos in the tunnel and layout

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Fig. 4. Manjet tube and U-GIP injection pipe

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Fig. 5. Principle of U-GIP injection pipe

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Fig. 6. Numerical model

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Fig. 7. Result of discharge and pore pressure

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Fig. 2. Fan Grouting

Table 1. Evaluation of leakage

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Table 2. Ground design parameters

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Table 3. Result of pore pressure and discharge at position of grouting

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References

  1. Cheon, B.S., Lee, Y.J., Ko, G.S., Jung, H.C., Choi, S.H. (1995), "Chemical grouting of tunnel underpassing the Han river", Proceedings of the Korean Society of Civil Engineers Conference, Seoul, Vol. 2, pp. 377-380.
  2. Do, I.W. (2014), "Performance research on cutoff grouting around the tunnel", M.S. Thesis, Graduate School of Kyungpook National University, pp. 1-49.
  3. Joo, E.J., Kim, Y.K., Shin, J.H., Kwon, O.Y. (2010), "Numerical study for the optimum grouting design of subsea tunnels", Journal of Korean Tunnelling and Underground Space Association, Vol. 12, No. 5, pp. 349-358.
  4. Seo, K.W., Baek, K.H., Kim, W.K., Jun, S.K., Kim, S.J. (2010), "Analysis of the grouting effectiveness in tunnel excavation", Proceedings of the Korean Society of Civil Engineers 36th Annual Conference, Incheon, pp. 1720-1723.
  5. You, K.H. (2011), "Analysis on the effect of strength improvement and water barrier by tunnel grouting reinforcement", Journal of Korean Tunnelling and Underground Space Association, Vol. 13, No. 4, pp. 291-304. https://doi.org/10.9711/KTAJ.2011.13.4.291
  6. You, K.H., Jie, H.K., Seo, K.W., Kim, S.J., You, D.W. (2012), "A study on the correlation between the rock mass permeability before and after grouting & injection volume and the parameters of Q system in a jointed rock mass tunnel", Journal of Korean Tunnelling and Underground Space Association, Vol. 14, No. 6, pp. 617-635. https://doi.org/10.9711/KTAJ.2012.14.6.617