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Effect of Steam Curing on the Properties of Recycled Aggregate Concrete

증기양생이 순환골재 콘크리트의 특성에 미치는 영향

  • 이승태 (군산대학교 토목공학과) ;
  • 최진엽 (군산대학교 토목공학과) ;
  • 박기태 (한국건설기술연구원 인프라구조연구실) ;
  • 서동우 (한국건설기술연구원 인프라구조연구실) ;
  • 유영준 (한국건설기술연구원 인프라구조연구실)
  • Received : 2013.09.30
  • Accepted : 2013.11.19
  • Published : 2014.03.30

Abstract

In this study, the effects of curing procedures on the mechanical properties of recycled aggregate concrete (RAC) were investigated. The replacement ratios by recycled coarse aggregate were 0, 25, 50, 75 and 100% by mass of natural coarse aggregate. Steam curing was adopted to all recycled aggregate concrete mixtures. Compressive and split tensile strength, water porosity, chloride ions penetration resistance and drying shrinkage measurements were carried out to determine performance of the RACs. From the test results, it was found that the mechanical performance of RAC decreased as the recycled aggregate contents increased. Furthermore, steam curing reduced the compressive and split tensile strength, water porosity and total charge of RAC, especially at the early ages. However, at the later ages, the beneficial effect of steam curing was less prominent. This study clearly showed that initial steam curing could be one of practical methods to improve performance of RAC with higher replacement ratio of recycled aggregate.

본 연구에서는 순환골재 콘크리트의 성능에 대한 양생방법의 영향에 대하여 실험적으로 고찰하였다. 순환골재 콘크리트 제조를 위하여 부순골재에 순환골재를 0, 25, 50, 75 및 100%로 대체하였으며, 증기양생한 콘크리트의 압축 및 쪼갬인장강도, 투수공극, 염소이온 침투저항성 및 건조수축을 소정의 재령에서 측정하여 수중양생한 콘크리트의 성능과 비교하였다. 실험결과에 따르면, 양생방법에 관계없이 순환 골재 대체율이 증가할수록 콘크리트의 역학적 성능은 감소하였다. 한편, 초기재령에서 증기양생된 콘크리트는 수중양생된 콘크리트와 비교하여 매우 우수한 성능을 나타내었다. 그러나, 장기재령 (28일)에서 증기양생의 효과는 초기재령에 비하여 두드러지게 나타나지 않음을 알 수 있다. 결론적으로, 본 연구의 범위 내에서 순환골재 콘크리트의 성능향상을 위하여 증기양생법의 적용이 유용할 것으로 판단된다.

Keywords

References

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