Fire Science and Engineering (한국화재소방학회논문지)

Korean Institute of Fire Science and Engineering (한국화재소방학회)
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A Prediction Model on Porosity of Hardened Cement Paste under High Temperatures

고온시의 경화된 시멘트 페이스트의 공극률 예측모델

  • Published : 2009.06.30
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Abstract

The thermal degradation of concrete results mainly from two mechanisms. The first one is related to phase transformations of constituents at different temperatures. The initial constituents transform to other phases due to elevated temperature. The second mechanism is related to the temperature sensitivity of the mechanical properties of the constituents in concrete. Therefore, the degradation of concrete under high temperatures must be studied from both mechanical and chemical points of view. This study was performed as a basic study to propose the material models of concrete exposed to high temperatures considering above two mechanisms. This study presents a prediction model on the porosity of hardened cement paste considering phase changes according to temperature increase.

콘크리트의 온도에 의한 재료적 특성에 대한 저감은 두 가지 메커니즘에 기인한다. 첫 번째 메커니즘은 온도범위에 따른 구성성분의 상변화이다. 초기 구성성분들은 온도 증가로 인해 다른 성분들로 상변화를 일으킨다. 두 번째 메커니즘은 온도에 의한 각 구성성분의 역학적 특성 변화이다. 따라서 고온에 노출된 콘크리트의 재료적 특성에 관한 모델 역시 이 두 가지 메커니즘을 함께 고려하여 제시되어야 한다. 본 연구는 위에서 언급한 두 가지 메커니즘을 고려한 고온에 노출된 콘크리트의 재료적 특성 모델을 제안하기 위한 기반연구로서, 온도범위에 따른 상변화를 고려한 경화된 시멘트 페이스트의 공극률에 대한 이론적 모델을 제시한다.

Keywords

References

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