A proposal and evaluation of a revised GIN method

Myung Sagong; Youngjin Park

doi:10.9711/KTAJ.2021.23.3.151

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2021 Vol.23, Issue 3 Preview Page Next Page

Research Paper

A proposal and evaluation of a revised GIN method 수정 GIN 기법의 제안 및 검증

31 May 2021. pp. 151-165

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Abstract

Grouting, which is applied for the increase of ground strength and the decrease of permeability, is complex process because of several reasons, so the process needs to be elaborated. Injection process in consideration of ground condition and optimization of grouting sequence is essential. In this study, GIN (Grouting Intensity Number), multiple of injected grout volume and pressure, is revised to consider injection pressure reduction and joint opening during grouting process. A revised GIN process is evaluated through a field test. A revised GIN, considering ground condition, injection pressure, follows GIN envelope and produces rational grouting process. The result of a revised GIN reduces permeability of the ground in the order of 10^-1~10^-2 cm/sec.

Keywords

Grouting

GIN

Rock joint

Frictional resistance

Joint opening

차수 및 보강을 목적으로 암반 내 수행되는 그라우팅은 여러가지 이유로 어려운 작업공정 이므로 세밀하게 수행되어야 한다. 가시적으로 확인이 불가능한 불연속면의 틈 사이로 주입되는 그라우트의 주입거동을 최적화 하면서 지반조건에 대응하는 주입방법의 도출이 필요하다. 본 연구에서는 주입압과 주입재 체적의 곱인 GIN (Grouting Intensity Number)를 보완하여 JRC에 따른 주입압의 감소 현상 및 주입압력으로 인한 절리의 열림 현상을 고려한 수정 GIN 기법을 제안하였다. 해당 방법에 대한 검증을 위하여 현장시험을 수행하였으며 지반조건에 대응하는 GIN의 산정 및 주입압과 주입양의 제어를 통해서 GIN의 한계를 준용하여 주입을 수행하였다. 그 결과 합리적인 그라우팅 작업의 수행이 가능하였으며 지반의 투수계수 또한 10^-1~10^-2 cm/sec 수준의 저감을 보였다.

키워드

그라우팅

GIN

암반절리

마찰 저항

절리 열림

References

Bandis, S.C., Lumsdent, A.C., Barton, N.R. (1983), “Fundamentals of rock joint deformation”, International Journal of Rock Mechanics and Mining Sciences & Geomchanics Abstract, Vol. 20, No. 6, pp. 249-268. 10.1016/0148-9062(83)90595-8

Chun, B.S., Choi, D.C., Kim, J.C. (2008), “An experimental study on the improving reliability of grouting by using p-q-t chart analyzing technique”, Journal of Korean Tunnelling and Underground Space Association, Vol. 10, No. 4, pp. 383-395.

Jeon, K.H., Ryu, D.W., Kim, H.M., Park E.S., Song, J.J. (2010), “Numerical analysis of grout flow and injection pressure affected by joint roughness and aperture”, Tunnel and Underground Space, Vol. 20, No. 2, pp. 82-91.

Lombardi, G. (1996), “Selecting the grouting intensity”, The International Journal on Hydropower & Dams, Vol. 4, pp. 62-66.

Sagong, M., Ryu, S.H. (2018), “Numnerical analyses using CFD on the pressure losses of the grout flow with variation of joint roughness and grout features”, Journal of Korean Tunnelling and Underground Space Association, Vol. 20, No. 6, pp. 989-1002.

Shahzad, M.I., Afridi, N.Z., Jadoon, T.A., Ahmad, S., Khan, J. (2017), “A case study of trial grouting using grouting intensity number (GIN) and conventional method at Tarbela 4^th foundation Tarbela dam”, Journal of Geotechnical and Transportation Engineering, Vol. 3, No. 2, pp. 47-51.

Turcote, L., Savard, B., Lombardi, G., Jobin, H. (1994), “The use of stable grout and G.I.N. technique in grouting for dam rehabilitation”, Proceedings of the Annual Meeting Canadian Dam Safety Conference CSDA and CANCOLD Winnipeg, Manitoba, pp. 137-161.

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 : 23
No :3
Pages :151-165
Received Date : 2021-03-30
Revised Date : 2021-05-13
Accepted Date : 2021-05-14
DOI :https://doi.org/10.9711/KTAJ.2021.23.3.151

Journal of Korean Tunnelling and Underground Space Association ISSN:2233-8292(Print) 2287-4747(Online) 한국터널지하공간학회 논문집

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