Journal of the Korean Recycled Construction Resources Institute (한국건설순환자원학회논문집)

Korean Recycled Construction Resources Institute (한국건설순환자원학회)
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Investigation on Fire Resistance of High-Performance Cement Motar with Recycled Fine Aggregate Mixed by Two-Stage Mixing Approach

2단계 배합을 사용한 순환잔골재 혼입 고성능 시멘트 모르타르의 내화성능 연구

  • Park, Sung-Hwan (Department of Architectural and Fire Protection Engineering, Pukyong National University) ;
  • Choi, Jun-Ho (Department of Fire Protection Engineering, Pukyong National University) ;
  • Lee, Chi Young (Department of Fire Protection Engineering, Pukyong National University) ;
  • Koo, Min-Sung (Department of Fire Protection Engineering, Pukyong National University) ;
  • Chung, Chul-Woo (Department of Architectural Engineering, Pukyong National University)
  • 박성환 (부경대학교 건축.소방공학부) ;
  • 최준호 (부경대학교 소방공학과) ;
  • 이치영 (부경대학교 소방공학과) ;
  • 구민성 (부경대학교 소방공학과) ;
  • 정철우 (부경대학교 건축공학과)
  • Received : 2021.12.06
  • Accepted : 2021.12.16
  • Published : 2022.03.30
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Abstract

This study was conducted to confirm the applicability of recycled aggregates as aggregates for structural concrete as a way to respond to the shortage of natural aggregates. The two-stage mixing approach developed by Tam et al. is known to be a method that can improve the mechanical performance of recycled aggregate concrete without the installation of new additional facilities. In this work, modified version of two stage mixing approach, which was used in our earlier work, was introduced to prepare mortar specimens with recycled fine aggregate, and the compressive strength and fire resistance were compared to mortar mixed with normal mixing approach. According to the experimental results from mortar with recycled fine aggregate, the use of two-stage mixing approach was found to be more effective than normal mixing approach for compressive strength development. In addition, the residual strengths of the mortar with two-stage mixing approach was higher than mortar made of normal mixing approach after exposure to 600 and 900 ℃. It is possible to manufacture high-performance cement composites with recycled fine aggregates through the active use of the two-stage mixing approach.

본 연구는 천연골재 부족사태에 대응하기 위한 방법으로, 콘크리트 구조물에 구조용 골재로서 순환골재의 재활용 가능성을 확인하기 위하여 진행되었다. Tam et al.에 의해 개발된 2단계 배합은 별도의 설비 등의 추가 없이 순환골재 혼입 시멘트 복합체의 역학적 성능을 향상시킬 수 있는 방법으로 알려져 있는데, 본 연구에서는 선행연구에서 확인한 개선된 형태의 2단계 배합방법을 활용하여 순환잔골재 혼입 모르타르 시험체를 제작하고, 이를 통해 배합방법의 차이가 순환잔골재 혼입 고강도 모르타르의 압축강도 및 내화성능에 미치는 영향을 확인하고자 하였다. 실험결과에 따르면 순환잔골재 사용시 일반배합 보다 2단계 배합방법을 활용하는 것이 순환잔골재 혼입 모르타르의 강도발현에 더욱 효과적인 것으로 나타났으며, 600 ℃ 및 900 ℃의 고온에 노출시켜 역학적 성능의 변화를 확인한 결과 2단계 배합을 활용하는 경우 모르타르의 잔존강도가 일반배합을 활용한 모르타르의 잔존강도보다 높게 나타나는 결과를 보였다. 이는 2단계 배합의 적극적 활용을 통해서, 순환잔골재로 고성능 시멘트 복합체의 제조가 가능함을 의미한다.

Keywords

Acknowledgement

이 논문은 2021년도 국립대학육성사업 지원비에 의하여 연구되었다. 실험의 준비 및 실험과정에서 손정진, 김성우, 최유진 학생의 도움에 감사드린다.

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