DOI QR코드

DOI QR Code

A Study on Optimum Proportion of FA and BS for Ternary Cement

3성분계 시멘트에서 FA 및 BS의 최적혼합비율 도출에 관한 연구

  • Han, Cheon-Goo (Department of Architectural Engineering, Cheong-ju University) ;
  • Park, Sung-Bae (Department of Architectural Engineering, Cheong-ju University)
  • Received : 2016.05.20
  • Accepted : 2016.06.08
  • Published : 2016.06.30

Abstract

The aim of research is inducing the optimum proportion of fly ash(FA) and blast furnace slag(BS) for ternary cement. In this research, hence, the fundamental properties of mortar mixtures were evaluated depending on various proportion of FA and BS. The results of the experiment, within the scope of the study, obtained the following conclusions. Flow of the mixtures was increased with addition of binary supplementary cementitious material(SCM), and especially, portion of FA. The air content of the mixtures was increased with addition of binary SCMs, while it was decreased with increased FA content. In the case of unit mass, increased value was obtained due to the increased air content within 25 to 45% of binary SCM content, while it was increased within 65 to 100% of binary SCM up to only 20% of FA content and decreased more than 20% of FA because of the low density of FA. The setting time of the mixtures was delayed with addition of binary SCM and FA. In the case of compressive strength, at 91-day age, the highest value was obtained with 25 and 45% of binary SCM with the proportion of FA to BS of 40 to 60. Therefore, based on the compressive strength, it is considered that the binary SCM content of 25 and 45% with the proportion of FA to BS of 2 : 3 is the most favorable conditions in this research scope.

본 연구는 3성분계 시멘트에서 FA와 BS의 최적혼합비율을 도출하기 위한 것이다. 즉, 혼화재 치환율 별 FA 및 BS의 다양한 혼합비율에 따른 모르타르의 기초적 특성을 파악하고자 하였다. 실험결과, 본 연구의 범위 내에서 다음과 같은 결론을 얻었다. 플로의 경우는 혼화재 치환율 및 FA의 혼합비율이 증가함에 따라 증가하는 것으로 나타났다. 공기량은 혼화재 치환율이 증가하고 FA의 혼합비율이 증가할수록 감소하였다. 단위용적질량은 혼화재 치환율 25% 및 45%에서는 공기량이 감소할수록 증가하는 것으로 나타났지만, 65% 및 100%에서는 FA 치환율 20%까지는 증가하였지만 그 이상에서는 FA의 저밀도 영향으로 감소하였다. 응결시간은 혼화재 치환율 및 FA의 혼합비율이 증가함에 따라 지연되는 것으로 나타났다. 압축강도의 경우는 재령 91일에 혼화재치환율 25% 및 45%에서 FA : BS의 비율이 40 :t 60인 배합에서 가장 우수한 강도 값을 나타내었다. 따라서 압축강도적인 측면을 종합적으로 고려할 때 혼화재 치환율 25% 및 45%인 경우에서 FA : BS의 비율 2 : 3인 경우가 본 연구의 범위 내에서는 최적의 혼합비율인 것으로 판명되었다.

Keywords

References

  1. Beak, C.W., Kim, H.S., Choi, S.W., Jo, H.T., Ryu, D.H. (2015). Durability assessment of high strength concrete with high volume mineral admixture, Journal of the Korea Concrete Institute, 27(6), 641-649 [in Korean]. https://doi.org/10.4334/JKCI.2015.27.6.641
  2. Choi, S.J., Jeon, Y.S. (2015). The fluidity and hardened properties of eco-friendly low cement concrete with 3types of binders, Journal of the Architectural Institute of Korea, 31(11), 63-70 [in Korean].
  3. Han, M.C. (2009). Effect of mineral admixture types on the engineering properties and the drying shrinkage of the concrete, Journal of the Korea Institute of Building Construction, 9(5), 121-127 [in Korean]. https://doi.org/10.5345/JKIC.2009.9.6.121
  4. Jeon, K.N., Lee, J.A., Choi, S.Y., Baek, D.H., Han, M.C., Han, C.G. (2009). "Improving quality of fly ash replace concrete by second-class blast furnace slag powder and gypsum," Proceeding of the Korea Institute of Building Construction, 9(1), 97-100 [in Korean].
  5. Song, Y.L., Zhao, Y., Min, K.C., Han, D.Y., Han, M.C., Han, C.G. (2015). "Hydration reactivity between blast furnace slag and fly ash," Proceeding of Korea Concrete Institute, 27(1), 451-452 [in Korean].