한국구조물진단유지관리공학회 논문집 (Journal of the Korea institute for structural maintenance and inspection)

  • 제23권5호
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  • Pages.30-36
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  • 2019
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  • 2234-6937(pISSN)
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  • 2287-6979(eISSN)
한국구조물진단유지관리공학회 (Korea Institute for Structural Maintenance Inspection)
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촉진 염화물 시험결과를 이용한 비말대 콘크리트 구조물의 내구수명 평가

Service life evaluation in RC structure near to sea shore through accelerated chloride diffusion test

  • 김정수 (한화건설 기술연구소) ;
  • 권성준 (한남대학교 건설시스템공학과)
  • 투고 : 2018.12.21
  • 심사 : 2019.05.27
  • 발행 : 2019.09.01
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초록

염해에 노출된 콘크리트 구조물의 내구수명을 정량적으로 평가하기 위해서는 사용 배합을 통하여 확산계수를 평가하고 이를 이용한 염화물 침투 해석이 필요하다. 본 연구에서는 비말대에 노출된 콘크리트 구조물에 대하여 촉진 확산계수를 NT BUILD 492 및 ASTM 1202를 통하여 평가하였으며, 기존의 연구를 이용하여 겉보기 확산계수를 도출하였다. 사용배합의 특성과 가장 보수적인 조건인 임계 염화물량과 표면 염화물량을 고려하였으며, Life 365 ver.2 프로그램을 이용하여 외벽 및 기둥구조의 내구수명을 평가하였다. 10년 및 15년의 Built-up period의 변화에 대해서는 내구수명은 큰 차이를 보이지 않았으며. 슬래그를 사용한 두 개의 배합에서는 높은 시간의존성 지수와 낮은 초기 염화물 확산계수로 인해 75년 이상의 높은 내구수명이 확보되었다.

In order to evaluate service life of RC (Reinforced Concrete) structures exposed to chloride attack, chloride penetration analysis is required referred to the chloride diffusion coefficient from the actual mix proportions. In this work, accelerated diffusion coefficients are obtained from NT BUILD 492 and ASTM C 1202 and the related apparent diffusion coefficients are derived via the previously proposed relationship for RC structures near to sea shore. Considering the properties of the mix proportions and the most conservative analysis conditions like critical and surface chloride contents, service lifes in column and exterior wall member are evaluated through conventional program LIFE 365 ver.2. The different built-up period of 10 and 15 years has no significant effect on service life. The results from mix proportions with slag show longer than 75 years of service life with the help of higher time dependent parameter and lower initial diffusion coefficient.

키워드

참고문헌

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