Journal of the Korea Concrete Institute (콘크리트학회논문집)

Korea Concrete Institute (한국콘크리트학회)
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Effect of Curing Conditions on the Strength of Fly-Ash Based Geopolymer

양생조건이 플라이애쉬 기반 지오폴리머 강도에 미치는 영향

  • Cho, Young-Keun (High-tech Construction Materials Center, Korea Conformity Laboratories) ;
  • Moon, Gyu-Don (High-tech Construction Materials Center, Korea Conformity Laboratories) ;
  • La, Jung-Min (High-tech Construction Materials Center, Korea Conformity Laboratories) ;
  • Jung, Sang-Hwa (High-tech Construction Materials Center, Korea Conformity Laboratories)
  • 조영근 (한국건설생활환경시험연구원, 첨단건설재료센터) ;
  • 문규돈 (한국건설생활환경시험연구원, 첨단건설재료센터) ;
  • 라정민 (한국건설생활환경시험연구원, 첨단건설재료센터) ;
  • 정상화 (한국건설생활환경시험연구원, 첨단건설재료센터)
  • Received : 2014.02.07
  • Accepted : 2014.04.21
  • Published : 2014.08.30
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Abstract

Material properties of geopolymer, whose the reaction is very complicated, have been influenced by chemical compositions and particle size distributions of fly ash, concentrations and types of alkali-activators and curing conditions such as temperatures and time. In this research, experiments with several variables such as curing temperatures, preset prior to the high temperature curing and high temperatures have been conducted in order to evaluate to investigate effects on the compressive strengths of geopolymer caused by curing condition. Experiment results were evaluated with compressive strengths and micro-structures such as SEM and MIP of geopolymer pastes. As a result, as higher curing temperature or longer preset time were applied to the pastes, higher compressive strengths were observed. However, compressive strengths of geopolymer pastes declined due to increases in macropores (>50 nm) under high temperatures elapsed after 24 hours. In this sense, it can be considered that strengths and microstructures of geopolymers depends on curing temperature and time.

지오폴리머 반응은 매우 복잡하며, 플라이애쉬 화학조성, 입도분포, 자극제 농도와 종류, 양생온도, 양생시간 등이 지오폴리머 물성에 많은 영향을 미치고 있는 것으로 알려져 있다. 이 연구에서는 양생조건이 플라이애쉬 기반 지오폴리머 강도에 미치는 영향을 실험하기 위하여, 양생온도, 고온양생 전 전치시간, 고온에서의 양생시간 등을 변화시켜 양생조건 변화에 따른 지오폴리머 페이스트의 압축강도, SEM, 공극특성 등에 대하여 분석하였다. 실험 결과 양생온도가 높을수록 지오폴리머의 강도는 증가하였으며, 전양생시간이 길어질수록 지오폴리머 강도는 증가되었으나, 고온양생에서의 양생시간이 길어지면 압축강도가 저하현상이 관찰되었다. 고온에서의 양생시간이 길어지면 공극구조의 변화에 따라 강도 저하 현상이 관찰되었다. 따라서 양생온도와 양생시간은 지오폴리머 강도 및 미세구조에 큰 영향을 미치고 있는 것을 확인할 수 있었다.

Keywords

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