Journal of the Korea Concrete Institute (콘크리트학회논문집)

Korea Concrete Institute (한국콘크리트학회)
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The Analysis of Early Age Properties of Hydration Heat and Autogenous Shrinkage according to Specimen Size and Retardation of Hydration

시험체 크기 및 수화지연 효과에 따른 초기재령 수화발열 및 자기수축 특성 분석

  • Kim, Gyu-Yong (Dept. of Architectural Engineering, College of Engineering, Chungnam National University) ;
  • Koo, Kyung-Mo (Dept. of Architectural Engineering, College of Engineering, Chungnam National University) ;
  • Lee, Hyoung-Jun (Dept. of Architectural Engineering, College of Engineering, Chungnam National University) ;
  • Lee, Eui-Bae (Dept. of Architectural Engineering, College of Engineering, Chungnam National University)
  • Published : 2009.08.31
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Abstract

It has been reported that the magnitude and the development rate of autogenous shrinkage of cement paste, mortar and concrete were affected by history and magnitude of inner temperature at an early age. But it was not enough to explain the relation between hydration heat and autogenous shrinkage at an early age, because there was no certain analysis on histories of hydration heat and autogenous shrinkage in previous studies. In our prior study, to understand the relationship between hydration heat and autogenous shrinkage of concrete at an early age, the analysis method for histories of hydration heat and autogenous shrinkage was suggested. Based on this method, early age properties of hydration heat and autogenous shrinkage of high strength concrete with different sizes and hydration retardation were investigated in this study. As a result of the study, properties of hydration temperature and autogenous shrinkage were different according to specimen size and hydration retardation. However, there was a close relationship between hydration temperature and autogenous shrinkage at an early age, especially between HHV and ASV as linear slopes of the sections where hydration temperature and autogenous shrinkage increase rapidly; the higher HHV, the higher ASV and the greater ultimate autogenous shrinkage. And it was found that, among the setting time, bend point and temperature increasing point, they were close relationship each other on cement hydration process.

시멘트페이스트, 모르타르 및 콘크리트의 자기수축의 크기 및 발현율은 초기재령 내부온도의 이력과 크기에 의해 영향을 받는다고 보고된 바 있으나, 초기재령 수화열과 자기수축에 대한 구체적인 관계분석은 아직 미흡한 실정 이다. 이 연구에서는 초기재령 수화온도 및 자기수축의 이력특성에 대한 분석방법을 제시한 선행연구를 기초로, 시험체 크기 및 수화지연 효과에 따른 고강도콘크리트의 초기재령 수화열과 자기수축의 거동특성 및 상관관계를 분석하였다. 또한 자기수축에 의한 균열평가시 유효자기수축의 기준이 되는 응결시간과 수화온도 및 자기수축의 이력과의 관계도 검토하였다. 그 결과, 시험체가 매스화될수록 초기재령 수화발열 상승구간의 수화온도 상승량 및 수화발열 상승속도, 자 기수축 증가구간의 자기수축 증가량 및 자기수축 속도는 증가하는 것으로 나타났으며, 지연제를 사용할 경우 그 값은 감소하는 것으로 나타났다. 초기재령 콘크리트의 수화발열 상승속도가 증가하면 자기수축 속도는 증가하며, 이와 더불 어 재령 91일 자기수축도 증가하는 것으로 나타나, 종국 자기수축은 초기재령 수화발열상승 속도에 의해 영향을 받을 수 있을 것으로 사료된다. 한편, 콘크리트 균열평가시 유효자기수축의 기준이 되는 응결시간과 변곡점 및 수화온도 상 승시점은 시멘트의 수화반응 과정에 있어 서로 밀접한 관계가 있음을 확인할 수 있었다.

Keywords

References

  1. Bjontegaard, O., Sellevold E. J., and Hammer, T. A., “High Performance Concrete at Early Ages: Selfgenerated Stresses Due to Autogenous Shrinkage and Temperature,” In the Int. Semina : Self-Desiccation and its Importance in Concrete Technology, Lund, Sweden, 1997, pp. 1-7
  2. 堀田 知明, 名和 豊春, “セメント一系材料の自己縮に関する硏究,” 日本建築学会構造系論文集, 542 , 2001, pp. 9-15
  3. Loukili, A., Chopin, D., Khelidj A., and Touzo, J. L., “A New Approach to Determine Autogenous Shrinkage of Mortar at an Early Age Considering Temperature History,”Cement and Concrete Research, Vol. 30, No. 6, 2000, pp. 915-922 https://doi.org/10.1016/S0008-8846(00)00241-6
  4. Shima, T., Matsuda, T., Koide, T., Kawakami, H., Suzuki, Y., and Nishimoto, Y., “Autogenous Shrinkage Characteristic of Ultra High-Strength Concrete Cured under High Temperature (Part1. Experimental Result and ShrinkageDecrease Effect by Expansive Admixture),” Proceeding of the Architechtural Research Meetings of AIJ, 2006, pp. 69-70
  5. コンクリ一ト工協会, “自己縮究委員報告書,” 1996, pp. 114-122
  6. Princigallo, A., Lura, P., Breugel, K. V., and Levita, G., “Early Development of Properties in a Cement Paste: A Numerical and Experimental Study,” Cement and Concrete Research, Vol. 33, No. 7, 2003, pp. 1013-1020 https://doi.org/10.1016/S0008-8846(03)00002-4
  7. 김규용, 이의배, 구경모, 최형길, “초기재령 고강도콘크리트의 수화발열과 자기수축 특성의 상관관계에 관한 기초적 연구,” 콘크리트학회 논문집, 20권, 5호, 2008, pp. 593-600 https://doi.org/10.4334/JKCI.2008.20.5.593
  8. Atcin. P. C., “Autogenous Shrinkage Measurement, Autogenous Shrinkage of Concrete,” Ed. E. Tazawa, E&FN Spon, 1999, pp. 257-268
  9. 이회근, 임준영, 이광명, 김병기, “플라이애쉬를 함유한 고성능 콘크리트의 자기수축,” 콘크리트학회 논문집, 14권, 2호, 2002, pp. 249-256 https://doi.org/10.4334/JKCI.2002.14.2.249
  10. 이광명, 권기현, 이회근, 이승훈, 김규용, “고로슬래그를 함유한 콘크리트의 자기수축 특성,” 콘크리트학회 논문집, 16권, 5호, 2004, pp. 621-626 https://doi.org/10.4334/JKCI.2004.16.5.621
  11. Lee, H. K., Lee, K. M., Kim, Y. H., Yim, H., and Bae, D. B., “Ultrasonic In Situ Monitoring of Setting Process of High-Performance Concrete,” Cement and Concrete Research, Vol. 34, No. 4, 2004, pp. 631-640 https://doi.org/10.1016/j.cemconres.2003.10.012

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  1. Comparison on Characteristics of Concrete Autogenous Shrinkage according to Strength Level, Development Rate and Curing Condition vol.23, pp.6, 2011, https://doi.org/10.4334/JKCI.2011.23.6.741