KSCE Journal of Civil and Environmental Engineering Research (대한토목학회논문집)

Korean Society of Civil Engeneers (대한토목학회)
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Compressive Strength of Concrete due to Moisture Conditions of Recycled Coarse Aggregates and Curing Conditions

순환 굵은 골재의 함수상태와 양생조건에 따른 콘크리트의 압축강도

  • Received : 2019.07.04
  • Accepted : 2019.07.22
  • Published : 2019.08.01
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Abstract

In this study, the effect of moisture conditions of recycled coarse aggregates on the compressive strength of concrete was evaluated with the water/binder ratios and the curing conditions. The saturated recycled aggregates seemed to have the negative effect on the strength development of concrete. This is the because of the decrease in bond strength between aggregate and cement paste due to the increase of surface water according to the high absorption of recycled aggregates. The effect of types and moisture conditions of aggregates according to the change of water/binder ratio was similar. However, the curing conditions had a significant effect on the compressive strength of the concrete with the different types of aggregates. In the case of curing in air, the recycled aggregates with high absorption reduced the moisture required for hydration and increased the rate of vaporizing, and these result in interfering strength development. The moisture conditions of the recycled aggregates have a considerable effect on the compressive strength of the concrete, and it is necessary to control the moisture conditions of aggregates in the production of concrete with recycled coarse aggregate. And the control of the curing condition is very important for the concrete with recycled aggregate.

본 연구는 순환 굵은 골재의 함수상태가 콘크리트의 압축강도에 미치는 영향을 물/결합재 비와 양생 조건을 변수로 하여 평가하였다. 표건상태의 순환골재는 콘크리트의 강도발현을 저하시켰는데, 이는 순환골재의 높은 흡수율에 의한 표면수의 증가로 골재와 시멘트 페이스트 사이의 부착강도가 저하되었기 때문이다. 골재의 종류와 함수상태가 물/결합재 비의 변화에 따라 압축강도에 미치는 영향의 정도는 비슷하였다. 그러나 양생조건에 대해서는 골재의 종류에 따라 상당한 차이를 보였다. 대기양생을 시킨 경우 높은 흡수율을 가진 순환골재는 수화작용에 필요한 수분을 감소시키고, 수분증발을 증가시켜 강도발현을 저해하였다. 순환골재의 함수상태는 콘크리트의 압축강도에 상당한 영향을 줬으며, 순환골재콘크리트 생산시 골재의 흡수율에 따른 함수상태에 대한 관리가 필요하다. 또한 순환골재 콘크리트의 경우 적절한 품질관리를 위해 양생관리가 매우 중요하다.

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References

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