Journal of the Korean GEO-environmental Society (한국지반환경공학회 논문집)

Korean Geo-Environmental Society (한국지반환경공학회)
권호 표지
DOI QR코드

DOI QR Code

A Study on the Impermeable Effect by Grouting in the Subsea Tunnel

해저터널에서 주입에 의한 차수효과 연구

  • Kim, Seunghwan (Geotechnical Department, Dream ENG Co., Ltd.) ;
  • Lim, Heuidae (Department of Civil Engineering, Chungnam National University) ;
  • Yoon, Seongmin (Geotechnical Department, Dream ENG Co., Ltd.)
  • Received : 2017.03.20
  • Accepted : 2017.04.24
  • Published : 2017.06.01
Download PDF
⟨ Previous Next ⟩

Abstract

In this study, the effect of rock mass curtain grouting was investigated by analyzing the correlation between the parameters of the RMR & grout injection volume, Lugeon value & RQD, Lugeon value & cement injection volume. In order to investigate the effect of rock mass curtain grouting, we analyzed the grout injection volume of 315 curtain grouting holes at 9 tunnel face of NATM Subsea tunnels in gneiss area. The total grout injection volume in the Subsea tunnels study was slightly changed in some tunnels face but decreased with increasing the rating of parameters in spacing of discontinuity (R3, Js) and groundwater condition (R5). The geological anomalies of seismic survey (3D, TSP) and the inflow of probe hole were found to be more correlated of relative than the parameters of RMR. The unit injection volume was found to decrease with higher ratings in the parameters of the RMR except the weathering degree of the discontinuity (Jc, R4). The correlation between RQD and Lugeon values is not significant, but it can be confirmed that the Lugeon value tends to decrease as the RQD value increases.

본 연구에서는 편마암지역의 NATM 해저터널 막장 9개소에서 실시한 차수 주입홀 315공에 대한 주입재 주입량에 대하여 RMR 분류요소들과 주입재 주입량, 루전값과 RQD, 루전값과 시멘트 주입량의 상관관계를 분석하여 암반 차수 주입 효과를 연구하였다. 연구대상 해저터널에서 막장별 주입재 총주입량은 일부 막장에서 다소 변화폭은 있으나, 불연속면의 간격(R3, Js)과 지하수상태(R5)에서 분류요소의 평점이 높을수록 감소하는 것으로 나타났으며, 막장별 총주입량은 RMR 분류요소들보다는 탄성파탐사(3D, TSP)의 지질이상대 및 감지공의 유입량과 상관관계가 큰 것으로 나타났다. 단위주입량은 불연속면의 상태(Jc, R4)의 풍화도를 제외한 RMR 분류요소들에서 평점이 높을수록 감소하는 것으로 나타났다. RQD와 루전값은 상관관계가 크지 않으나, RQD 값이 클수록 루전값이 감소하는 경향을 확인할 수 있었다.

Keywords

References

  1. Barton, N. R. and Lunde, J. (1974), Engineering classification of rock masses for the design of tunnel support, Rock Mech, Vol. 6, pp. 183-236.
  2. Bieniawski, Z. T. (1989), Engineering rock mass classification a wiley-interscience publication, John Wiley & Sons, Inc., New York, p. 251.
  3. Do, J. N., Park, J. H., Choi, D. C. and Chun, B. S. (2012), A study on the field application of automatic grouting system, Journal of the Korean Geotechnical Society, Vol. 13, No. 1, pp. 63-74 (in Korean).
  4. Goodman (1965), Groundwater inflow during tunnel driving, Engineering Geology, pp. 39-56.
  5. Hong, W. P., Yun, J. M., Yeo, G. G. and Lee, H. (2002), The cut-off effect by rock grouting in the area of dam-foundation, The 2002 Annual Conference of Korean Society of Civil Engineers, Korean Society of Civil Engineers, pp. 2110-2113 (in Korean).
  6. Karol, R. H. (1961), Symposium on grouting, Grouting in flowing water and stratified deposits, Journal of soil mechanics and foundation engineering, ASCE, Vol. 87, pp. 125-145.
  7. Kong, J. Y., Kim, C. K., Park, J. H. and Chun, B. S. (2010), Grouting effects of microfine cement in the rock-based sites, Journal of the Korean Geotechnical Society, Vol. 11, No. 12, pp. 37-45 (in Korean).
  8. Lee, J. G. (2014), A study on the modification of GIN grouting method of subsea tunnel, masrer's thesis, Hanyang University, pp. 1-139 (in Korean).
  9. Seo, Y. H., Nam, H. Y., Ju, K. S., Jang, S. B., Hur, D. H. and Lee, S. C. (2010), An introduction of the design for the first subsea road tunnel (Boryeong tunnel) in Korea, The News Letter of Korean Tunnelling Association, Vol. 12, No. 3, pp. 30-38 (in Korean).
  10. Yang, C. P. (2004), Estimating cement take and grout efficiency on foundation improvement for Li-Yu-Tan dam, Engineering Geology, Vol. 75, Amsterdam, pp. 1-14. https://doi.org/10.1016/j.enggeo.2004.04.005
  11. Yea, G. G. (2009), The impermeable effect for bedrock constructed by grouting, Journal of the Korean Geotechnical Society, Vol. 10, No. 2, pp. 51-59 (in Korean).
  12. You, K. H., Jie H. G., Seo, K. W., Kim, S. J. and You, D. W. (2012), A study on the correlation between the rock mass permeability before and after grouting & injection volume and parameters of Q system in a joint rock mass tunnel, Journal of Korean Tunnelling and Underground Space Assoication, Vol. 14, No. 6, pp. 617-635 (in Korean). https://doi.org/10.9711/KTAJ.2012.14.6.617