Journal of the Korea Institute of Building Construction (한국건축시공학회지)

The Korean Institute of Building Construction (한국건축시공학회)
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Strength Correction Factors due to Temperature Drop of Structural Concrete under Low Temperature by the Equivalent Age Method

저온환경에서 타설되는 구조체 콘크리트의 등가재령 방법을 활용한 기온보정강도 설정

  • Choi, Youn-Hoo (Department of Architectural Engineering, Cheong ju University) ;
  • Han, Min-Cheol (Department of Architectural Engineering, Cheong ju University) ;
  • Lee, Young-Jun (Department of Architectural Engineering, Cheong ju University)
  • Received : 2019.11.30
  • Accepted : 2020.10.07
  • Published : 2020.10.20
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Abstract

In this paper, strength correction factors of the concretes incorporating ordinary Portland cement(OPC), fly ash(FA) and blast furnace slag(BS) with 50% of water to binder ratio due to temperature drop for standard room temperature(20±3℃) are provided. For this, strength development was done based on equivalent age method. For calculating the equivalent age, apparent activation energy was obtained with 24.69 kJ/mol in OPC, 46.59 kJ/mol in FA, 54.59 kJ/ol in BS systems. According to the estimation of strength development of the concretes, the use of FA and BS resulted in larger strength drop than that of OPC under low temperature compared to standard room temperature. Hence, strength correction factors(Tn) for OPC, FA and BS are suggested within 4~17℃ with every 3MPa levels.

본 연구는 W/C 50%의 일반강도 조건에서 OPC, FA 및 BS 시멘트의 종류를 변화시켜 콘크리트의 강도 증진 성상을 한랭기 온도의 4~17℃의 평균 양생온도에서 검토하고, 등가재령에 의한 강도 해석모델을 이용하여 강도 증진 해석을 수행하고, 기온저하에 따른 기온보정강도를 제안하고자 하였다. 본 실험의 결과 등가재령을 이용하여 Plowman 모델식으로 강도증진을 해석하였고, 대체로 양생온도가 낮을수록 강도증진이 지연되는 경향을 나타내었다. 이에 양생온도 저하에 따른 강도보정을 3MPa 단위로 실시하였고, 이를 토대로 배합강도 결정시 결합재 종류 및 관리재령별 기온보정강도(Tn)을 제안하였다.

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References

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