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Micro-silica Mixed Aqua-epoxy for Concrete Module Connection in Water : Part 1 - Material Development and Evaluation

해상 프리캐스트 콘크리트 부유체 모듈 가접합을 위한 마이크로 실리카 혼입 수중용 에폭시 접합 성능 검토 : Part 1 - 재료 개발 및 성능 검토

  • Choi, Jin-Won (School of Civil and Environmental Engineering, Yonsei University) ;
  • Kim, Young-Jun (School of Civil and Environmental Engineering, Yonsei University) ;
  • You, Young-Jun (School of Civil and Environmental Engineering, Yonsei University) ;
  • Kwon, Seung-Jun (Dept. of Civil Engineering, Hannam University) ;
  • Kim, Jang-Ho Jay (School of Civil and Environmental Engineering, Yonsei University)
  • 최진원 (연세대학교 사회환경시스템공학부) ;
  • 김영준 (연세대학교 사회환경시스템공학부) ;
  • 유영준 (연세대학교 사회환경시스템공학부) ;
  • 권성준 (한남대학교 건설시스템공학과) ;
  • 김장호 (연세대학교 사회환경시스템공학부)
  • Received : 2014.04.23
  • Accepted : 2014.11.11
  • Published : 2015.02.28

Abstract

Recent studies on concrete floating structure development focused on connection system of concrete modules. Precast concrete modules are designed to be attached by prestressing in the water, exposing the structure to the loads from water and making the construction difficult. Therefore, a development of bond material became a key issue in successful connection of floating concrete modules. In this study, micro-silica mixed aqua epoxy (MSAE) is developed for the task. Existing primer aqua epoxy, originally used as a bond material for the retrofit of concrete structures using fiber reinforced polymers, is evaluated to find the optimum micro-silica added mix proportion. Micro-silica of 0~4 volume % was mixed in standard mixture of aqua epoxy. Then, the material property tests were performed to study the effect of micro-silica in aqua epoxy by controlling the epoxy silane proportion by 0, ${\pm}5$, ${\pm}10%$. The optimum mix design of MSAE was derived based on the test results. The MSAE was used to connect concrete module specimens with the epoxy thickness variation of 5, 10, and 20mm. Then, 3-point loading test was performed to verify the bond capacity of MSAE. The results show that MSAE improves the bond capacity of concrete module.

최근에 콘크리트 모듈로 건설하는 부유 구조물에 대한 연구가 활발히 이루어짐에 따라 콘크리트 모듈 간 접합 공법에 대한 필요성이 대두되고 있다. 모듈 간 접합 작업은 수중에서 프리스트레싱 텐던을 긴장하여 이루어지므로 시공성이 저하될 가능성이 있어서 가접합을 위한 부착재료 개발이 요구된다. 이번 연구에서는 콘크리트 구조물 보수보강용 섬유보강 패널 부착에 사용된 수중용 에폭시에 $SiO_2$ 계열 마이크로 실리카(Micro-silica : MS)를 혼입하여 콘크리트 모듈 가접합용 접합재료를 개발, 평가하였다. 기존 수중용 에폭시에 0~4% MS를 혼입하여 부착성능 평가를 통하여 최적 MS 혼입량을 산정하였으며 수중용 에폭시의 점도에 따른 MS 혼입 효과를 확인하기 위하여 주제 비율을 각각 0, ${\pm}5$%, ${\pm}10%$로 조정하여 재료성능을 검토한 후 최적 비율을 도출하였다. 도출된 마이크로 실리카 수중용 에폭시(MSAE)의 콘크리트 모듈 접합 성능을 검증하기 위하여 콘크리트 모듈 접합 시험체에 3점 재하 실험을 실시한 결과 MSAE는 기존 수중용 에폭시에 비해 콘크리트 모듈 접합 성능이 크게 향상된 것으로 나타났다.

Keywords

References

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