Journal of the Korean Recycled Construction Resources Institute (한국건설순환자원학회논문집)

Korean Recycled Construction Resources Institute (한국건설순환자원학회)
권호 표지
DOI QR코드

DOI QR Code

Modeling of Material Properties of Fiber-Reinforced High Strength Concrete

섬유 보강 고강도 콘크리트의 재료 특성 모델링

  • Yang, In-Hwan (Department of Civil Engineering, Kunsan National University) ;
  • Park, Ji-Hun (Department of Civil Engineering, Kunsan National University) ;
  • Choe, Jeong-Seon (Department of Civil Engineering, Kunsan National University) ;
  • Joh, Changbin (Structural Engineering Research Institute, Korea Institute of Civil Engineering and Building Technology)
  • 양인환 (군산대학교 토목공학과) ;
  • 박지훈 (군산대학교 토목공학과) ;
  • 최정선 (군산대학교 토목공학과) ;
  • 조창빈 (한국건설기술연구원 인프라안전연구본부)
  • Received : 2018.11.20
  • Accepted : 2018.11.30
  • Published : 2018.12.30
Download PDF
⟨ Previous Next ⟩

Abstract

In this study, material properties of steel fiber reinforced high strength concrete (FRHSC) with the compressive strength of about 120MPa were modeled. Steel fiber content of 1.0%, 1.5%, and 2.0% was considered as experimental variable. First of all, compressive strength tests were carried out to determine compressive characteristics of concrete, and compressive stress-strain curves were modeled. For conventional concrete with moderate compressive strength, the stress-strain curves are in the form of parabolic curves, but in the case of high strength concrete reinforced with steel fiber, the curves increase linearly in the form of the straight line. In addition, to understand the tensile properties of FRHSC, the crack mouth opening displacement (CMOD) test was performed, and the tensile stress-CMOD curve was calculated through inverse analysis. When the steel fiber content increased from 1.0% to 1.5%, there was a significant difference of tensile strength. However, when the amount of steel fiber was increased from 1.5% to 2.0%, there was no significant difference of tensile strength, which might result from the poor dispersion and arrangement of steel fiber in concrete.

본 연구에서는 기준압축강도 120MPa의 강섬유 보강 고강도 콘크리트(FRHSC)의 재료 특성 모델링을 수행하였다. 실험변수로서 강섬유 혼입량을 1.0%, 1.5% 및 2.0%로 설정하였다. 우선, 콘크리트의 압축 거동 특성을 파악하기 위하여 압축강도 실험을 수행하였으며, 압축응력-변형률 곡선을 산정하였다. 보통 강도 콘크리트의 경우, 응력-변형률 관계는 곡선 형태로 나타나지만, 강섬유 보강 고강도 콘크리트의 경우 거의 직선으로 비례하여 증가하는 형상을 나타냈다. 또한, 콘크리트의 인장 특성을 파악하기 위해 균열개구변위(CMOD) 실험을 수행하고 역해석을 통하여 인장응력-CMOD 곡선을 산정하였으며, 이를 토대로 인장응력-변형률 관계 곡선을 모델링하였다. 강섬유 혼입량이 1.0%에서 1.5%로 증가할 때 인장강도는 뚜렷히 증가하였으나, 강섬유 혼입량이 1.5%에서 2.0%로 증가할 때 인징강도는 뚜렷한 차이를 나타내지 않았다. 이러한 실험결과는 강섬유의 분산성과 배열이 향상되지 않아 콘크리트 재료 특성에 영향을 주었기 때문이다.

Keywords

GSJHDK_2018_v6n4_349_f0001.png 이미지

Fig. 1. Shape of steel fiber( lf=16.5mm)

GSJHDK_2018_v6n4_349_f0002.png 이미지

Fig. 2. Test of compressive strength

GSJHDK_2018_v6n4_349_f0003.png 이미지

Fig. 3. Stress strain curve(vf=1.0%)

GSJHDK_2018_v6n4_349_f0004.png 이미지

Fig. 4. Stress strain curve(vf=1.5%)

GSJHDK_2018_v6n4_349_f0005.png 이미지

Fig. 5. Stress strain curve(vf=2.0%)

GSJHDK_2018_v6n4_349_f0006.png 이미지

Fig. 6. Stress strain curve modeling

GSJHDK_2018_v6n4_349_f0007.png 이미지

Fig. 7. Bottom face of CMOD test

GSJHDK_2018_v6n4_349_f0008.png 이미지

Fig. 8. Measurement setting of CMOD

GSJHDK_2018_v6n4_349_f0009.png 이미지

Fig. 9. Load-CMOD curve(vf=1.0%)

GSJHDK_2018_v6n4_349_f0010.png 이미지

Fig. 10. Load-CMOD curve(vf=1.5%)

GSJHDK_2018_v6n4_349_f0011.png 이미지

Fig. 11. Load-CMOD curve(vf=2.0%)

GSJHDK_2018_v6n4_349_f0012.png 이미지

Fig. 12. Tensile stress-CMOD curve(vf=1.0%)

GSJHDK_2018_v6n4_349_f0013.png 이미지

Fig. 13. Tensile stress-CMOD curve(vf=1.5%)

GSJHDK_2018_v6n4_349_f0014.png 이미지

Fig. 14. Tensile stress-CMOD curve(vf=2.0%)

GSJHDK_2018_v6n4_349_f0015.png 이미지

Fig. 15. Relationship between maximun load of CMOD and tensile strength

GSJHDK_2018_v6n4_349_f0016.png 이미지

Fig. 16. Tensile strength-strain curve(AFGC, 2013)

GSJHDK_2018_v6n4_349_f0017.png 이미지

Fig. 17. Comparison of tensile stress-strain modeling

Table 1. Mix proportions

GSJHDK_2018_v6n4_349_t0001.png 이미지

Table 2. Test results of compressive strength

GSJHDK_2018_v6n4_349_t0002.png 이미지

Table 3. Tensile stress results

GSJHDK_2018_v6n4_349_t0003.png 이미지

References

  1. AFGC/SETRA. (2002). Ultra High Performance Fibre-Reinforced Concretes, Recommandations Provisoires.
  2. Banthia, N., Sappakittipakorn, M. (2007). Toughness enhancement in steel fiber reinforced concrete through fiber hybridization, Cement and Concrete Research, 37(9), 1366-1372. https://doi.org/10.1016/j.cemconres.2007.05.005
  3. Chan, Y.W., Chu, S.H. (2004). Effect of silica fume on steel fiber bond characteristics in reactive powder concrete, Cement and Concrete Research, 34(7), 1167-1172. https://doi.org/10.1016/j.cemconres.2003.12.023
  4. DafStb. (2004). Ultra High Performance Concrete (UHPC), International Symposium on Ultra High Performance Concrete.
  5. Gowripalan, N., Gilbert, R.I. (2000). Design Guidelines for Ductal Prestressed Concrete Beams, The University of New South Wales.
  6. Graybeal, B.A. (2007). Compressive behavior of ultra-high-performance fiber-reinforced concrete, ACI Materials Journal, 104(2), 146-152.
  7. Graybeal, B.A. (2008). Flexural behavior of an ultra-high-Performance concrete I-girder, Journal of Bridge Engineering, 13(6), 602-610. https://doi.org/10.1061/(ASCE)1084-0702(2008)13:6(602)
  8. Graybeal, B.A., Russel, H.G. (2013). Ultra-High Performance Concrete: A State-of-the-Art Report for the Bridge Community, Federal Highway Administration, FHWA-HRT-13-060.
  9. JSCE. (2006). Recommendations for Design and Construction of Ultra High Strength Fiber Reinforced Concrete Structures (Draft), Research of Ultra High Strength Fiber Reinforced Concrete Japan Society of Civil Engineers, 9.
  10. Mohamadreza, S., MahsaFarzad, F., Atorod, A. (2017). Experimental and numerical study on mechanical properties of ultra high performance concrete(UHPC), Construction and Building Materials, 156(15), 402-411. https://doi.org/10.1016/j.conbuildmat.2017.08.170
  11. Naaman, A.E., Reinhardt, H.W. (2004). High performance fiber reinforced cement composites HPFRCC, Cement and Concrete Composites, 26(6), 757-759. https://doi.org/10.1016/j.cemconcomp.2003.09.001
  12. Yang, I.H., Joh, C.B., Kim, B.S. (2010). An experimental study on flexural behavior of steel fiber reinforced ultra high performance concrete prestressed girders, Journal of the Korea Concrete Institute, 22(6), 777-786 [in Korean]. https://doi.org/10.4334/JKCI.2010.22.6.777
  13. Yang, I.H., Kim, K.C., Joh, C.B. (2014). Structural behavior of hybrid steel fiber-reinforced ultra high performance concrete beams subjected to bending, Journal of the Korea Concrete Institute, 26(6), 771-778 [in Korean]. https://doi.org/10.4334/JKCI.2014.26.6.771
  14. Yang, I.H., Kim, K.C., Joh, C.B. (2015). Flexural strength of hybrid steel fiber-reinforced ultra-high strength concrete beams, Journal of the Korea Concrete Institute, 27(3), 280-287 [in Korean].
  15. Yuliarti, K., Ekkehard, F., Mohammed, I., Attitou, A.M.A. (2015). Tensile strength behavior of UHPC and UHPFRC, Procedia Engineering, 125, 1081-1086. https://doi.org/10.1016/j.proeng.2015.11.166