DOI QR코드

DOI QR Code

Mechanical Properties and Durability of Concrete Incorporating Air-Cooled Slag

서냉슬래그 미분말을 적용한 콘크리트의 역학적 성능 및 내구성 평가

  • Lee, Seung-Tae (Department of Civil Engineering, Kunsan National University) ;
  • Park, Kwang-Pil (Department of Civil Engineering, Kunsan National University)
  • Received : 2017.02.15
  • Accepted : 2017.03.10
  • Published : 2017.03.31

Abstract

Blast furnace slag(BFS) is a by-product generated during the manufacture of pig ion, and is divided into water-cooled slag(WS) and air-cooled slag(AS) by the coking method of BFS. In this study, concrete specimens with ternary binders were produced at the various replacement levels of cement by AS. Various mechanical properties of concrete, such as compressive and split tensile strengths, absorption and water permeable pore, were measured. In addition, the chloride ions penetration resistance and carbonation resistance were tested to evaluate the durability of concrete incorporating AS. The experimental data indicated that the use of AS up to a maximum of 10% replacement level enhanced the concrete performance. However, a higher replacement of AS exhibited poor mechanical properties and concrete durability.

고로슬래그는 제철과정에서 생산되는 산업부산물로써, 냉각방법에 따라 서냉슬래그와 급냉슬래그로 구분된다. 본 연구에서는 콘크리트 결합재로써 서냉슬래그를 시멘트에 대하여 부분 대체(0, 5, 10, 20, 30 및 40%)하여 삼성분계 시멘트 콘크리트 공시체를 제조하였으며, 강도, 흡수율, 투수공극량 등 콘크리트의 역학적 특성뿐 만 아니라, 염소이온 침투저항성, 탄산화 저항성 등 콘크리트의 내구성능을 실험적으로 평가함으로써, 서냉슬래그의 콘크리트용 혼화재료로써 적용 가능성에 대하여 고찰하고자 하였다. 본 연구를 통하여 도출된 실험결과로부터, 서냉슬래그를 약 10% 대체할 경우, 콘크리트의 성능은 만족할 만한 수준의 성능을 나타내는 것으로 조사되었다. 그러나, 서냉슬래그를 30% 이상 사용한 콘크리트는 결정질의 AS가 다량 대체됨으로 인하여 수화반응 및 포졸란 반응 등 결합재의 경화반응이 상대적으로 지연된 탓으로 인하여 역학적 성능 및 내구성이 다소 떨어지는 결과를 나타내었다. 따라서, AS를 콘크리트용 결합재로 적용하기 위한 최적 대체율이 존재하는 것으로 나타났으며, 건설재료의 경제적 및 환경적 관점에서 AS를 약 10% 정도까지 적용할 경우, 구조용 콘크리트 재료로써 적용이 가능할 것으로 판단된다.

Keywords

References

  1. T. Ozbakkaloglu, L. Gu, A. F. Pour, "Normal and high strength concretes incorporating air-cooled blast furnace slag coarse aggregates: Effect of slag size and content on the behavior", Construction and Building Materials, vol. 126, pp. 138-146, 2016. DOI: https://doi.org/10.1016/j.conbuildmat.2016.09.015
  2. Morioka, "Influence of fine powder of air-cooled blast furnace slag on fluidity and its mechanism", Cement Science and Concrete Technology. vol. 56, pp. 72-77, 2002.
  3. N. Y. Mostafa, S. A. S. El-Hemaly, E. I. Al-Wakeel, S. A. El-Korashy, P. W. Brown, "Hydraulic activity of water-cooled slag and air-cooled slag at different temperatures", Cement and Concrete Research, vol. 31, pp. 475-484, 2001. DOI: https://doi.org/10.1016/S0008-8846(00)00462-2
  4. N. Y. Mostafa, S. A. S. El-Hemaly, E. I. Al-Wakeel, S. A. El-Korashy, P. W. Brown, "Characterization and evaluation of the hydraulic activity of water-cooled slag and air-cooled slag", Cement and Concrete Research, vol. 31, pp. 899-904, 2001. DOI: https://doi.org/10.1016/S0008-8846(01)00497-5
  5. H. El-Didamony, A. A. Amer, T. M. El-Sokkary, H. Abd-El-Aziz, "Effect of substitution of granulated slag by air-cooled slag on the properties of alkali activated slag", Ceramic International, vol. 39, pp. 171-181, 2013. DOI: https://doi.org/10.1016/j.ceramint.2012.06.007
  6. NT BUILD 492, "Concrete, mortar and cement-based repair materials: Chloride migration coefficient from non-steady-state migration experiments", Finland, Nordtest, 1999.
  7. S. Y. Kang, "Study on Compressive Strength Development Properties of Concrete using Slow Cooling Ground Granulated Slag High-Powder", Master's thesis, Tongmyong University, 2004.
  8. M. F. M. Zain, Md. Safiuddin, H. Mahmud, "Development of high performance concrete using silica fume at relatively high water-binder ratios", Cement and Concrete Research, vol. 30, pp. 1501-1505, 2000. DOI: https://doi.org/10.1016/S0008-8846(00)00359-8
  9. J. H. Heo, S. U. Jung, J. W. Heo, N. G. Im, "Basic Properties of Concrete with Ultrafine-Blaine Air Cooling Slag as Admixture", Korea Institute of Building Construction, vol. 9, pp. 77-83, 2009. DOI: http://doi.org/10.5345/JKIC.2009.9.2.077
  10. X. Zhang, X. Zhou, H. Zhou, K. Gao, Z. Wang, "Studies on forecasting of carbonation depth of slag high performance concrete considering gas permeability", Applied Clay Science, vol. 79, pp. 36-40, 2013. DOI: https://doi.org/10.1016/j.clay.2013.02.020