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An experimental study for the effect of soil plug on the basal heave stability for the vertical shaft excavation in clay

점성토 지반 수직구 굴착 중 히빙 안정성 증가에 대한 관내토 효과에 대한 실험적 연구

Seok-Jun Kang1
,
Gye-Chun Cho2
,
Jung-Tae Kim3
,
Yohan Cha3
,
Eun-Soo Hong4*
강 석준1
,
조 계춘2
,
김 정태3
,
차 요한3
,
홍 은수4*
1Master’s Course, Dept. of Civil and Environmental Engineering, KAIST
2Professor, Dept. of Civil and Environmental Engineering, KAIST
3Ph.D. Candidate, Dept. of Civil and Environmental Engineering, KAIST
4Research Associate Professor, Dept. of Civil and Environmental Engineering, KAIST
1KAIST 건설 및 환경공학과 석사과정
2KAIST 건설 및 환경공학과 교수
3KAIST 건설 및 환경공학과 박사과정
4KAIST 건설 및 환경공학과 연구부교수
*교신저자. *Corresponding Author. 
31 January 2018. pp. 183-195
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Abstract

Recently, the need for research on vertical shaft excavation is increasing with the increase of the demands for the underground and utility tunnels. As a part of the R&D project of the Ministry of Land, Infrastructure and Transport, CUT (center for utility tunnel) has developed “Ring cut method”. “Ring cut method” is a method to improve the stability of the ground against the basal heave by excavator wall pre-penetration during vertical shaft excavation. In this study, the basal heave was simulated by centrifugal model test. The basal heave, ground subsidence, and ground deformation of surrounding ground were analyzed by soil plug effect from wall pre-penetration. It was found that the soil plug could control the basal heaving and ground subsidence, and verified that the ‘Ring cut method’ could be a good countermeasure for the ground stability against the basal heave.

Keywords
Vertical shaft
Excavation
Basal heave
Soil plug
Centrifugal model test

최근 공동구 및 지하터널의 수요증가와 함께 수직구 굴착에 대한 연구의 필요성이 증가하고 있다. 공동구 연구단은 국토교통부 연구개발사업의 일환으로 ‘수직구 외주면 선행 굴착공법 및 장비’를 개발하였으며 현재 성능 검증 중에 있다. ‘수직구 외주면 선행 굴착공법’은 수직구 굴착 시 굴착면의 외주면을 먼저 굴착하고 굴착기 벽체를 관입시켜 연약지반의 히빙에 대한 지반의 안정성을 확보하는 공법이다. 이 연구에서는 원심모형실험을 통해 히빙을 모사하고 관내토의 유무에 따른 지반면의 히빙과 지반침하, 그리고 주변지반의 거동을 비교, 분석하였다. 분석 결과 관내토가 지반침하와 히빙의 발생을 충분히 억제하는 효과를 나타내는 것으로 파악되었으며, 수직구 외주면 선행 굴착공법이 히빙에 대한 지반의 안정성을 충분히 확보함을 확인할 수 있었다.

키워드
수직구
굴착
히빙
관내토
원심모형실험
References
1
Aksoy, C.O. (2008), “Chemical injection application at tunnel service shaft to prevent ground settlement induced by groundwater drainage: A case study”, International Journal of Rock Mechanics and Mining Sciences, Vol. 45, No. 3, pp. 376-383.
2
ASTM. D. 2850-03a (2007), Standard Test Methods for Unconsolidated-Undrained Triaxial Compression Test on Cohesive Soils, ASTM International, West Conshohocken, PA, 2003, DOI: 10.1520/D2850-03AR07.
3
ASTM. D. 4318-93 (1994), Standard test method for liquid limit, plastic limit and plasticity index of soils. Annual Book of ASTM Standards 4, pp. 551-561.
4
ASTM. D. 6913-04 (2009), Standard test methods for particle-size distribution (gradation) of soils using sieve analysis.
5
Center for utility tunnel (2015), Development of core technology for urban small-diameter utility tunnel construction.
6
Goh, A.T.C. (1994), “Estimating basal-heave stability for braced excavations in soft clay”, Journal of Geotechnical Engineering, Vol. 120, No. 8, pp. 1430-1436.
7
Goh, A.T.C. (2017), “Basal heave stability of supported circular excavations in clay”, Tunnelling and Underground Space Technology, Vol. 61, pp. 145-149.
8
Hong, E.S., Cho, G.C., Baak, S.H., Jun, H.W. (2016), “Rapid construction technique development for vertical shafts of utility tunnels”, KTA 2016 Annual Spring Conference, Seoul, Korea, pp. 129-130.
9
Hsieh, P.G., Ou, C.Y., Liu, H.T. (2008), “Basal heave analysis of excavations with consideration of anisotropic undrained strength of clay”, Canadian Geotechnical Journal, Vol. 45, No. 6, pp. 788-799.
10
Khatri, V.N., Kumar, J. (2010), “Stability of an unsupported vertical circular excavation in clays under undrained condition”, Computers and Geotechnics, Vol. 37, No. 3, pp. 419-424.
11
Kim, D.S., Kim, N.R., Choo, Y.W., Cho, G.C. (2013), “A newly developed state-of-the-art geotechnical centrifuge in Korea”, KSCE Journal of Civil Engineering, pp. 77-84.
12
Kim, K.Y., Lee, D.S., Jeong, S.S. (2012), “Analysis of earth pressure acting on vertical circular shaft considering aching effect (I): a study on centrifuge model tests”, Journal of the Korean Geotechnical Society, Vol. 28, No. 2, pp. 23-31.
13
13.Schofield, A.N. (1980), “Cambridge geotechnical centrifuge operations”, Geotechnique, Vol. 30, No. 3, pp. 227-268.
14
14.Shin, Y.W., Park, T.S., Lee, I.K. (2005), “A method of estimating earth pressure on a shaft wall and ground settlement caused by excavation”, KSCE Tunnel Committee Special Conference, pp. 151-167.
15
Shin, Y.W., Sagong, M. (2007), “A rational estimating method of the earth pressure on a shaft wall considering the shape ratio”, Journal of Korean Tunnelling and Underground Space Association, Vol. 9, No. 2, pp. 143-155.
16
Taylor, R.N. (1995), “Centrifuges in modelling: principles and scale effects”, Geotechnical Centrifuge Technology, pp. 19-33.
17
Terzaghi, K., Peck, R.B. (1948), Soil mechanics in engineering practice, John Wile and Sons, New York.
18
Thielicke, W., Stamhuis, E.J. (2014), “PIVlab-towards user-friendly, affordable and accurate digital particle image velocimetry in MATLAB”, Journal of Open Research Software, Vol. 2, No. 1, pp. 30.
Information
  • Publisher :Korean Tunneling and Underground Space Association
  • Publisher(Ko) :한국터널지하공간학회
  • Journal Title :Journal of Korean Tunnelling and Underground Space Association
  • Journal Title(Ko) :한국터널지하공간학회 논문집
  • Volume : 20
  • No :1
  • Pages :183-195
  • Received Date : 2017-12-12
  • Revised Date : 2017-12-26
  • Accepted Date : 2018-01-03
  • DOI :https://doi.org/10.9711/KTAJ.2018.20.1.183
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