Journal of the Korea Institute of Building Construction (한국건축시공학회지)

The Korean Institute of Building Construction (한국건축시공학회)
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Proposals for Revision of Lightweight Aggregate Concrete Specifications Based on In-situ Quality Control on Concrete

현장 품질관리를 고려한 경량골재 콘크리트의 시방서 개정안에 대한 고찰

  • Lee, Kyung-Ho (Department of Architectural Engineering, Graduate School, Kyonggi University) ;
  • Yang, Keun-Hyeok (Department of Architectural Engineering, Kyonggi University)
  • Received : 2017.11.09
  • Accepted : 2018.03.12
  • Published : 2018.06.20
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Abstract

This study examined the reliability and revision necessity of concrete standard specifications based on the comparisons with test data obtained by using domestic artificial lightweight aggregates and the contents specified in different foreign specifications including ACI 211.2, ACI 213, ACI 301, JASS 5 and CEB-FIP. To achieve the continuous particle distribution of domestic fine lightweight aggregates, the partial addition of natural sand with the maximum size of 2.5mm was required. To control the segregation and excessive bleeding in the fresh lightweight concrete, the current limitations on the water-to-binder ratio and unit water content need to be modified using lower values. In particular, a rational mixture proportion approach of lightweight concrete needs to be established for the targeted requirements of initial slump, 28-day compressive strength, air content and dry unit weight. Ultimately, significant revision of the concrete standard specifications is required considering the characteristics of domestic artificial lightweight aggregates.

이 연구에서는 국내산 인공 경량골재를 사용한 콘크리트의 실험결과를 바탕으로 콘크리트 표준시방서의 관련내용에 대한 합리성 및 개정의 필요성을 평가하였다. 국내 표준시방서의 내용은 ACI 211.2, ACI 213, ACI 301, JASS 5 및 CEB-FIP 시방내용들과 비교하였다. 국내산 인공 경량 잔골재의 연속적 입도분포를 위해서는 최대직경 2.5mm 이하의 천연모래 혼입이 요구되었다. 경량골재 콘크리트의 재료분리 및 과도한 블리딩을 제어하기 위해서는 현재 시방서에서 제시된 최대 물-결합재비와 단위수량에 대한 수정이 요구되었다. 특히, 배합 목표성능인 초기 슬럼프, 28일 압축강도, 공기량 및 기건 단위용적중량에 대해 경량골재 콘크리트의 합리적인 배합설계 절차의 확립이 요구되었다. 결과적으로 콘크리트 표준시방서는 국내산 인공 경량골재의 특성을 고려하여 전반적이 개정이 요구되었다.

Keywords

References

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