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Carbonation Properties of Ordinary Concrete Exposed for 15 Years

15년간 노출 시험한 일반 콘크리트의 탄산화 특성 검토

  • Lee, Binna (Department of Structural Engineering Research, KICT) ;
  • Lee, Jong-Suk (Department of Structural Engineering Research, KICT)
  • 이빛나 (한국건설기술연구원 구조연구본부) ;
  • 이종석 (한국건설기술연구원 구조연구본부)
  • Received : 2022.09.02
  • Accepted : 2022.09.19
  • Published : 2022.09.30

Abstract

In this study, Long-term test specimens were tested in the outdoor exposure environment and the carbonation properies of concrete were analyzed. The test specimens were manufactured in 40 %, 50 % and 60 % according to the w/c ratio. Carbonation was measured at 3 years and 15 years of age. Based on the results, long-term carbonation prediction models(KICT model) were derived. As a result, carbonation increased according to the w/c. Based on the w/c 40 %, w/c 50 % increased about 1.8 times and w/c 60 % increased about 3.7 times. Comparison of carbonation according to age was that the carbonation at 15th year was about 3 times higher that of 3rd year. As results of comparing the KICT models and other carbonation prediction models, the carbonation prediction showed different values.

본 연구에서는 국내 환경에서 장기간 옥외 노출 시험을 수행하였으며 이 중 콘크리트의 탄산화 특성에 대해 분석하였다. 시험체는 물/시멘트비에 따라 40 %, 50 % 및 60 %로 총 3종류를 대상으로 수행하였으며, 재령 3년차 및 재령 15년차의 탄산화 측정 및 분석하였으며 이를 대상으로 장기 탄산화 예측 모델을 도출하여 국내외 탄산화 예측 모델과 비교·분석하였다. 분석결과, 물/시멘트비에 따라 탄산화가 증가하는 경향을 보였으며 물/시멘트비 40 %를 기준으로 물/시멘트비 50 %의 경우 약 1.8배, 물/시멘트비 60 %의 경우 약 3.7배 증가하였다. 재령에 따른 탄산화를 비교한 결과 기존 문헌처럼 재령에 따라 증가하는 경향을 보였으며 본 시험체의 경우 재령 15년차 탄산화 값이 재령 3년차 기준 약 3배 정도 높게 나타났다. 본 연구에서 실측한 탄산화를 바탕으로 국내외 탄산화 예측 모델과 비교한 결과 기존 예측 모델과 많은 차이를 보이고 있으며, 추후 지속적으로 데이터를 확보하여 검증 및 개선할 예정이다.

Keywords

Acknowledgement

본 연구는 과학기술정보통신부 한국건설기술연구원 연구운영비지원사업(주요사업)인 '국민 안전과 건전한 인프라 환경을 위한 지속가능한 인프라 구조 기술 연구(수행과제번호: 20220263-001)'과제에 의해 수행되었습니다.

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