Evaluation of tensile properties of SFRC for TBM tunnel segment

Do-Young Moon; Soo-Ho Chang; Gyu-Jin Bae; Gyu-Phil Lee

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2012 Vol.14, Issue 3 Preview Page Next Page

Evaluation of tensile properties of SFRC for TBM tunnel segment TBM 터널 세그먼트용 강섬유보강 콘크리트의 인장특성 평가

31 May 2012. pp. 247-260

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Abstract

In order to reduce the amount of steel reinforcements in TBM tunnel segments, the use of Steel Fiber Reinforced Concrete(SFRC) is being tried. The steel fibers with higher aspect ratio than that used in tunnel shotcrete are preferred to compensate the deficiency in tensile strength of the segments. In this study, the tensile properties of SFRC with aspect ratio of steel fibers equal to 80 were evaluated through flexural test and Double Punch Test. In the results of flexural test, flexural strengths of the SFRC were increased about 30%~150% thanks to bond of steel fibers used to concrete and could be properly predicted by the equation proposed by Oh(2008). There was a great difference in the estimated direct tensile strengths of the SFRC by the equations presented in ACI and RILEM. It was found that the Double Punch Test could be suitable methodology to estimate the direct tensile strength presented in RILEM of the SFRC.

Keywords

Double punch test

tensile strength

SFRC

TBM 터널 세그먼트의 철근량을 감소시키기 위한 연구로서, 강섬유 보강콘크리트의 사용이 시도되고 있다. 이와 같은 터널 세그먼트에는 철근의 감소로 인해 필요한 인장성능의 확보를 위하여 숏크리트에 사용되는 강섬유에 비해 매우 높은 형상비의 강섬유를 활용하는 것이 필요하다. 본 연구에서는 강섬유의 형상비가 80인 강섬유 콘크리트의 인장특성을 휨시험과 Double Punch Test를 통해 평가하였다. 휨시험결과, 사용된 강섬유의 충분한 부착강도로 인해 30%~150%의 강도 증진을 나타냈으며, 오영훈(2008)의 예측식을 통한 휨인장강도예측이 가능한 것으로 판단된다. 이 실험을 근거로 설계에 필요한 직접인장강도를 ACI와 RILEM의 식에 의해 평가한 결과, 적용기준에 따라 큰 차이가 있는 것으로 나타났다. 또한, DPT 실험을 통해 RILEM에서 권고하고 있는 직접인장강도의 정밀도 있는 예측이 가능한 것으로 판단 된다.

키워드

Double punch test

인장강도

강섬유 보강 콘크리트

References

1.김상명, 신진용, 마상준, 남관우, 김기호 (2008), “숏크리트 구성재료에 따른 콘크리트 성능에 관한 실험적 연구”, 한국터널지하공간학회 논문집, Vol. 10, No. 1, pp. 59-68.

2.문도영, 이규필, 장수호, 배규진 (2011), “강섬유보강 콘크리트 세그먼트의 강섬유가 표면전기저항에 미치는 영향”, 한국터널지하공간학회 논문집, Vol. 13, No. 6, pp. 557-569.

3.송용수, 류종현, 임희대 (2010), “숏크리트의 조기강도에 대한 실험적 연구”, 한국터널지하공간학회 논문집, Vol. 12, No. 4, pp. 285-294.

4.오영훈 (2008), “갈고리형 강섬유를 혼입한 보통 힘 및 고강도 콘크리트의 휨강도 평가”, 콘크리트학회 논문집, Vol. 20, No. 4, pp. 531-539.

5.KS F 2405 (2005), “콘크리트의 압축강도 시험방법”, 한국표준협회.

6.KS F 2566 (2010), “강섬유 보강 콘크리트의 휨인성 시험방법”, 한국표준협회.

7.ASTM C 1609M (2007), “Standard test method for flexural performance of Fiber-Reinforced Concrete (Using beam with Third-Point loading)”, ASTM.

8.Chiaia, B, Fantilli, A. P., Vallini, P. (2009), “Combining fiber-reinforced concrete with traditional reinforcement in tunnel linings”, Engineering Structures, Vol. 31, pp. 1600-1606.

9.Cho, S.H., Karki, N.B., Cho, J.S., Waweru, R.N. (2012), “Use of Double Punch Test to Evaluate the Mechanical Performance of Fiber Reinforced Concrete”, HPFRCC6, pp. 27-34.

10.Dobashi, H., Konishi, Y., Nakayama, M., Matsubara, K. (2006), “Development of steel fiber reinforced high fluidity concrete segment and application to construction”, Tunneling and Underground Space Technology, Vol. 21, p. 422.

11.Malatesta, S.C., Aguado, A., Molins, C., Cabrera, M. (2009), “Quality control of fiber reinforced concretes by mean of double punshing test (barcelona test)”, Revista Ingenieria de Construccion, Vol. 24, No. 2, pp. 119-140.

12.Malatesta. S.C., Aguado, A., Molins, C. (2012), “Generalization of the Barcelona test for the toughness control of FRC”, Materials and Structures, RILEM 2011.

13.Mangat, P.S., Gurusamy, K. (1987), “Long-term properties of steel fibre reinforced marine concrete”, Materials and Structures, Vol. 20, pp. 273-282.

14.Molins, C., Aguado A., Saludes, S. (2008), “Double Punch Test to control the energy dissipation in tension of FRC (Barcelona test)”, Materials and Structures, Vol. 42, No. 4, p. 415.

15.RILEM TC 162-TDF (2003), “

http://static.apub.kr/journalsite/sites/kta/2012-014-03/N0550140306/images/PICBB6.gif

design method-final recommendation”, Materials and Structures, Vol. 36, pp. 560-567.

16.Song, P.S., Hwang, S. (2004), “Mechanical Properties of High-Strength Steel Fiber-Reinforced Concrete”, Construction and Building Materials, Vol. 18, pp. 669-673.

17.Wafa, F.F., Ashour, S.A. (1992), “Mechanical Properties of High-Strength Fiber Reinforced Concrete”, ACI materials Journal, Vol. 89, No. 5, pp. 449-455.

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 : 14
No :3
Pages :247-260
Received Date : 2012-05-01
Revised Date : 2012-05-10
Accepted Date : 2012-05-18

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

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