대한토목학회논문집 (KSCE Journal of Civil and Environmental Engineering Research)

  • 제33권2호
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  • Pages.475-481
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  • 2013
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  • 1015-6348(pISSN)
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  • 2799-9629(eISSN)
대한토목학회 (Korean Society of Civil Engeneers)
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저온 소성한 MgO 분말을 함유한 플라이애시 콘크리트의 기본 물성

Fundamental Properties of Fly ash Concrete Containing Lightly Burnt MgO Powder

  • 최슬우 (성균관대학교 건설환경시스템공학과) ;
  • 장봉석 (한국수자원공사 K-water연구원) ;
  • 이광명 (성균관대학교 건설환경시스템공학과)
  • 투고 : 2012.12.26
  • 심사 : 2013.03.07
  • 발행 : 2013.03.30
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초록

$850{\sim}1000^{\circ}C$ 정도의 저온에서 소성된 MgO 분말을 적정량 치환한 콘크리트는 장기팽창성을 갖는다. 이러한 팽창성은 저온소성한 MgO 분말의 느린 수화반응을 통해 이루어지기 때문에 장기재령까지 수축을 보상하는 특성을 가진다. 최근 수화열 저감, 내구성 향상 등의 이유와 함께 건설 산업의 탄소저감을 위한 방안으로 플라이애시 및 고로슬래그 등과 같은 혼화재의 사용이 증가하고 있다. 따라서 저온소성한 MgO 분말을 팽창재로 사용하기 위해서는 이러한 혼화재와 MgO 분말을 함께 사용한 콘크리트의 특성 규명이 필요하다. 이 연구에서는 플라이애시 콘크리트에 저온소성한 MgO 분말을 치환한 콘크리트의 슬럼프, 공기량, 수화열뿐만 아니라 장기재령 압축강도 및 길이변화 등의 기본 물성을 실험을 통해 조사하였다. 단열온도 상승시험 결과, 5% 수준으로 MgO 분말을 치환한 콘크리트의 단열온도상승속도 및 최종온도가 플라이애시 콘크리트보다 다소 작게 나타났다. 또한 압축 강도 실험결과 물-결합재비에 따라 저온소성한 MgO 분말이 장기재령 압축강도에 미치는 영향이 다르게 나타났으며, 장기적인 길이변화 실험 결과 저온소성한 MgO 분말을 치환한 콘크리트에서 큰 팽창효과를 확인할 수 있었다.

Although the lightly burnt MgO at $850{\sim}1000^{\circ}C$ has expansibility, it does not lead to unsound concrete. The expansion of MgO could compensate for shrinkage of concrete for a long-term, because the hydration of MgO occurs at a slow pace. Recently, the study and application of mineral admixture such as fly ash and blast furnace slag have increased for the hydration heat reduction, durability improvement, and reducing $CO_2$ emission in the construction industry. Thus, it is necessary to research on the concrete that contains both a mineral admixture and MgO as an expansion agent. This study investigates fundamental properties of fly ash concrete with lightly burnt MgO through various experiments. The adiabatic temperature test results showed that the fly ash concrete with MgO of the 5% replacement ratio had the slower pace of the temperature rise and the lower final temperature than the fly ash concrete. The influences of MgO on long-term compressive strength varied depending on water-binder ratio, and the long-term length change test results indicated the expansion effects of the FA concrete containing MgO.

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참고문헌

  1. Amaral, L.F., Oliveira, I.R., Salomao, R., Frollini, E., Randolfelli, V.C. (2010) "Temperature and common-ion effect on magnesium oxide (MgO) hydration", Ceramics International, Vol. 36, No. 3, pp. 1047-1054. https://doi.org/10.1016/j.ceramint.2009.12.009
  2. Beaudoin, J.J., Ranachandran V.S. (1975) "Strength development in magnesium oxychloride and other cements", Cement and Concrete Research, Vol. 5, No. 6, pp. 617-630. https://doi.org/10.1016/0008-8846(75)90062-9
  3. Choi, S.W., Oh, S.H., Kim, D.W., Lee, K.M., Jang, B.S. (2011) "A Study on the Early Hydration-Retarding of Cement Composites Containing MgO", 2011 Proceedings of the Korea Concrete Institute, Korea Concrete Institute, Vol. 23, No. 1, pp. 341-342 (in Korean).
  4. Du, C. (2005) "A Review of Magnesium Oxide in Concrete", Concrete International, Vol. 27, No. 12, pp. 45-50.
  5. Gao, P., Lu, X., Geng, F., Li, X., Hou, J., Lin, H., Shi, N. (2008) "Production of MgO-type expansive agent in dam concrete by use of industrial by-products", Building and Environment. Vol. 43, No. 4, pp. 453-457. https://doi.org/10.1016/j.buildenv.2007.01.037
  6. He, Y.W., Huang, X.T. (2002) "Application of MgO Concrete to Promote Development of Dam Construction", Guangdong Water Resources and Hydropower, June 2002 (Supplement), pp. 3-4. (in Chinese)
  7. Jang, B.S., Kwon, Y.G., Choi, S.W., Lee, K.M. (2011) "Fundamental Properties of Cement Composites Containing Lightly Burnt MgO Powders", Journal of Korea Concrete Institute, Vol. 23, No. 2, pp. 225-233 (in Korean). https://doi.org/10.4334/JKCI.2011.23.2.225
  8. Kim, J.K., Yang, E.I. (1997) "Factors for Hydration Heat and Thermal Stress in Mass Concrete", Journal of Korea Concrete Institute, Vol. 9, No. 3, pp. 15-23 (in Korean).
  9. Kim, J.K., Park, Y.D., Sung, K.Y. (1991) "The Long-Term Strength and the Workability of High-Strength Fly Ash Concrete", Journal of Korea Concrete Institute, Vol. 3, No. 4, pp. 107-115 (in Korean).
  10. Korean Agency for Technology and Standards (2006) KS L 5201 Portland cement.
  11. Lee, C.Y., Choi, S.H., Kang, S.H., Lee, K.M. (1999) "Influence of Fly Ash Content with Respect to the Fresh and Mechanical Properties in Concrete", Journal of Korea Concrete Institute, Vol. 11, No. 6, pp. 25-33 (in Korean).
  12. Lee, H.K., Im, J.Y., Lee, K.M., Kim, B.G. (2002) "Autogenous Shrinkage of High Performance Concrete Containing Fly Ash", Journal of Korea Concrete Institute, Vol. 14, No. 2, pp. 249-256 (in Korean). https://doi.org/10.4334/JKCI.2002.14.2.249
  13. Leshchinsky, M.Y., Velichko, V.A. (1991) "The use of fly ash in concrete subject to heat", Cement and concrete research, Vol. 21, No. 2/3, 1991, pp. 205-218. https://doi.org/10.1016/0008-8846(91)90001-X
  14. Liu, X., Li, Y. (2005) "Effect of MgO on the composition and properties of alite-sulphoaluminate cement", Cement and Concrete Research, Vol. 35, No. 9, pp. 1685-1687. https://doi.org/10.1016/j.cemconres.2004.08.008
  15. Liu, Z., Cui, X., Tang, M. (1992) "Hydration and Setting Time of MgO-type Expansive Cement", Cement and Concrete Research, Vol. 22, No. 1, pp. 1-5. https://doi.org/10.1016/0008-8846(92)90129-J
  16. Metha, P.K., Monteiro, P.J. (2006) Concrete : Structure, Properties, and Materials, McGraw-Hill, USA.
  17. Mo, L., Deng, M., Tang, M. (2010) "Effects of calcination condition on expansion property of MgO-type expansive agent used in cement-based materials", Cement and Concrete Research, Vol. 40, No. 3, pp. 437-446. https://doi.org/10.1016/j.cemconres.2009.09.025
  18. Naik, T.R., Singh, S.S., Hossain, M.M. (1994) "Permeability of concrete containing large amount of fly ash", Cement and concrete research, Vol. 24, No. 5, 1994, pp. 913-922. https://doi.org/10.1016/0008-8846(94)90011-6
  19. Salomao, R., Bittencourt L.R.M., Pandolfelli, V.C. (2007) "A novel approach for magnesia hydration assessment in refractory castables", Ceramics International, Vol. 33, No. 5, pp. 803-810. https://doi.org/10.1016/j.ceramint.2006.01.004
  20. Shen, S.L., Zhu, G.B., Huang, X.T., Liu, J.H. (2003) "Construction Procedure for Arch Dams of MgO Concrete without Contraction Joints", Guangdong Water Resources and Hydropower, Dec 2003, pp. 1-4. (in Chinese)
  21. Wang, W.Q., Huang, X.T. (2002) "Quality Control for Construction of a Double-Arch Dam of MgO Concrete", Guangdong Water Resources and Hydropower, June 2002 (Supplement), pp. 10-12. (in Chinese)
  22. Xu, J.B., Huang, X.T. (2002) "Fast Construction Procedure for Arch Dams without Contraction Joints", Guangdong Water Resources and Hydropower, June 2002 (Supplement), pp. 8-9. (in Chinese)
  23. Zhou, R.M. (2003) "Profit Analysis of Arch Dam Construction Using MgO Concrete", Guangdong Water Resources and Hydropower, Dec 2003, pp. 5-7. (in Chinese)

피인용 문헌

  1. Durability characteristics of fly ash concrete containing lightly-burnt MgO vol.58, 2014, https://doi.org/10.1016/j.conbuildmat.2014.01.080