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

Korea Institute for Structural Maintenance Inspection (한국구조물진단유지관리공학회)
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An Experimental Study on Characteristics of Flexural Behavior in RC Member with Mineral Admixture under Calcium Leaching Degradation

칼슘용출 열화 조건에서 광물질 혼화재를 사용한 RC부재의 휨 거동에 관한 실험적 연구

  • Received : 2017.08.23
  • Accepted : 2017.11.30
  • Published : 2018.03.01
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Abstract

Concrete is a suitable construction material for long-term structure, however, it is needed to understand the calcium leaching damage caused by exposure to underground pure water for a long time. In this paper, it is experimentally investigated that the characteristics of flexural behavior in RC member damaged by calcium leaching degradation. From the test results, when calcium leaching is happened, yielding load and flexural rigidity is reduced, neutral axis depth and displacement is increased. That is, calcium leaching degradation adversely affects RC member performance. And, when the mineral admixture is used in the calcium leaching environment, it is considered that the optimal replacement ratio should be prepared according to the type of mineral admixture.

콘크리트는 장기수명이 요구되는 구조물에 적합한 건설재료로 내구성이 우수하지만 장기간 지하수에 노출되어 발생하는 칼슘용출 현상에 대한 이해 및 이에 따른 RC 부재의 휨 거동 특성을 평가할 필요가 있다. 실험결과에 따르면, 광물질 혼화재는 RC 부재의 장기강도 개선에 효과적이지만, 칼슘용출이 발생하면 RC 부재의 항복하중 및 휨 강성이 감소하고 중립축깊이와 처짐량이 증가하는 것으로 나타났다. 따라서 칼슘용출에 의한 열화는 RC 부재의 성능 저하를 유발하므로 칼슘용출 환경에 노출되는 지하구조물에 광물질 혼화재가 적용될 경우에는, 광물질 혼화재 종류에 따른 최적 혼입 비율이 마련되어야할 것으로 사료된다.

Keywords

References

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