KSCE Journal of Civil and Environmental Engineering Research (대한토목학회논문집)

Korean Society of Civil Engeneers (대한토목학회)
권호 표지

A Numerical Study on the Characteristics of Plastic Shrinkage Cracking of Concrete Slab

콘크리트 슬래브의 소성수축균열 특성에 대한 해석적 연구

Kwak, Hyo-Gyoung;Ha, Soo-Jun
곽효경;하수준

  • Published : 2005.11.30

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Abstract

In this paper, the influence of many factors related to the concrete mixture and the weather condition on plastic shrinkage cracking are analyzed through parametric studies using the numerical models introduced in the companion paper. First of all, through a systematic calculation of bleeding, the relationship between the bleeding constants and concrete mixture is proposed on the basis of the experimental data obtained by many researchers. Moreover, an equation, which can directly determine a critical point at which the evaporation and bleeding is balanced, is introduced, and the efficiency of the introduced equation is verified through the correlation study between the obtained results by the introduced equations and those by the rigorous analyses. The introduced equations can effectively be used to predict and to prevent plastic shrinkage cracking without any rigorous analysis and, in advance, to cope with the sudden changes in the concrete mixture and/or weather condition.

본 논문에서는 본 논문의 1편에서 제안된 소성수축균열 해석모델을 이용해 소성수축균열에 대한 물-시멘트비, 단위수량, 잔골재율, 슬래브 두께, 외기온도, 외기습도, 풍속, 타설온도 저감량의 상대적인 영향을 비교, 분석하였다. 먼저 소성수축균열 해석을 수행하기에 앞서 타 연구자들이 수행한 콘크리트 블리딩 실험으로부터 얻어진 실험결과를 바탕으로 블리딩 해석상수와 블리딩에 영향을 미치는 영향인자와의 관계를 규명하였다. 나아가 소성수축균열 해석결과를 바탕으로 블리딩수 완전 증발시기와 이 때의 수분증발량에 대한 모델식을 제안하여 영향인자에 따른 소성수축균열 발생 특성을 정량적으로 규명함으로써 실제 시공 현장에서 콘크리트 배합 및 외기조건에 따라 소성수축균열 발생 가능성을 예측하고 이에 대한 대비를 할 수 있도록 하였다.

Keywords

References

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