메뉴 건너뛰기
.. 내서재 .. 알림
소속 기관/학교 인증
인증하면 논문, 학술자료 등을  무료로 열람할 수 있어요.
한국대학교, 누리자동차, 시립도서관 등 나의 기관을 확인해보세요
(국내 대학 90% 이상 구독 중)
로그인 회원가입 고객센터 ENG
주제분류

추천
검색

논문 기본 정보

자료유형
학위논문
저자정보

박기철 (동명대학교, 동명대학교 대학원)

지도교수
임남기
발행연도
2015
저작권
동명대학교 논문은 저작권에 의해 보호받습니다.

이용수5

표지
AI에게 요청하기
추천
검색

이 논문의 연구 히스토리 (2)

초록· 키워드

오류제보하기
최근 콘크리트구조물이 대형화·거대화·초고층화 되면서 이들 구조물의 내구성능 확보 및 향상을 통한 콘크리트구조물의 장수명화에 대한 사회적인 요구가 점점 증대되고 있다. 하지만, 최근 급격한 환경기후변화에 의한 알카리 골재반응, 중성화, 염해, 황산염, 탄산화, 동결융해, 건조수축, 화학물질 등의 조기열화요인에 기인하는 콘크리트구조물의 내구성능 저하가 커다란 사회문제로 부각되고 있다.
이중에서도 가장 심각한 형태의 열화요인으로 최근 염화물이온의 침투에 기인하는 철근콘크리트구조물의 부식에 따른 내구성 저하가 커다란 해결과제로 지목되고 있다. 이에 대한 대책으로 최근 염화물이온의 침투 및 확산에 기인(起因)하는 콘크리트구조물의 내구성 향상 및 저하 대책으로 콘크리트구조물의 장기내구성을 목적으로 FA 또는 BFS를 혼입한 콘크리트의 적극적인 적용이 검토되면서 이들 재료를 혼입한 콘크리트의 역학적 특성 및 우수한 염분침투저항성이 주목 받고 있다.
본 연구에서는 FA 또는 BFS를 다량 혼입한 콘크리트의 염분침투성에 대해 검토하였다. 즉, 분말도가 각각 다른 FA 또는 BFS를 시멘트의 중량 치환으로 30, 50, 70%까지 치환하는 방법으로 FA 또는 BFS 콘크리트의 역학적 특성 및 염분침투성을 검토하였다. 또한, 시뮬레이션(NIST)에 의한 압축강도 및 확산계수의 정량적 예측·평가를 실시하여 시뮬레이션의 활용 가능성을 검토하였다. 본 연구에서의 결과는 다음과 같다.
(1) FA 콘크리트의 경우 OPC 콘크리트 대비 전체적으로 강도는 낮은 경향을 나타내는 것으로 파악되었으나, 강도증가율에서는 OPC 대비 동등이상의 증가율을 나타내는 것으로 확인되었다. 하지만, FA를 혼입한 콘크리트의 경우 분말도 및 치환율에 따라 각각 다른 경향을 나타내는 것으로 파악되어 배합단계에서의 FA 혼입에 대한 적절한 설정이 필요한 것으로 판단된다. 본 연구의 결과에서는 FA 콘크리트의 경우 분말도에 상관없이 FA를 30% 정도에서 치환하는 것이 강도증가 및 개선효과에 있어 가장 유효한 것으로 확인되었다.
(2) BFS 콘크리트의 경우 OPC 콘크리트 대비 동등이하의 강도를 나타내었으나, 분말도 및 치환율의 차이가 강도에 크게 영향을 미치는 것으로 파악되었다. 본 연구의 결과에서는 BFS6000 및 8000을 50% 혼입한 것이 OPC 대비 동등이상의 강도는 물론 강도증가율에서도 가장 유효한 거동을 나타내는 것으로 확인되었다. 이러한 경향은 고미분말의 BFS 혼입에 따른 마이크로 필라 효과가 크게 영향을 미친 것으로 판단된다.
(3) FA 콘크리트의 확산계수는 OPC 대비 전체적으로 높은 것으로 나타나 FA의 혼입에 따른 염분침투 억제 효과는 크게 없는 것으로 사료된다. 다만, FA4000 및 5000을 30% 혼입한 콘크리트의 경우 각각 4.8 및 7.3% 정도의 범위에서 확산계수를 억제하는 것으로 나타났다. 특히, FA5000을 혼입한 콘크리트의 억제 효과가 보다 우수한 것으로 나타나 FA의 경우 30% 이하의 혼입율에서는 분말도가 높은 고미분말의 혼입이 확산계수의 증가를 보다 효과적으로 억제할 수 있을 것으로 판단된다.
(4) BFS 콘크리트의 염분침투시험 결과에서는 BFS의 혼입에 따른 염분침투억제 효과가 파악되었다. 또한, BFS의 경우 분말도 및 치환율이 확산계수의 거동에 크게 영향을 미치는 것으로 나타났다. 본 연구의 결과에서는 BFS6000 및 8000을 혼입한 경우 OPC 콘크리트 대비 약 2.5 및 3배 이상 확산계수의 증가를 억제할 수 있을 것으로 확인되었다. 이러한 결과로부터 본 연구에서 염화물 이온의 침투저항을 목적으로 BFS를 혼입한 콘크리트의 유효성은 물론 다량 혼입에 따른 염분침투저항성을 보다 향상시킬 수 있을 것으로 판단된다. 본 연구의 결과에서는 BFS6000 및 8000을 각각 50% 혼입한 콘크리트의 염분침투저항성이 가장 우수한 것으로 확인되었다.
(5) FA 콘크리트의 역학적 특성과 확산계수의 관계에서는 강도가 증가할수록 확산계수는 감소하는 경향이 파악되었다. 본 연구 결과에서는 FA4000 및 5000을 30% 혼입한 경우가 OPC 대비 동등 정도의 강도 확보는 물론 염화물 이온의 확산을 목적으로 FA를 콘크리트에 혼입한 콘크리트로서의 성능을 만족하는 것으로 확인되었다.
(6) BFS 콘크리트의 역학적 특성과 확산계수의 관계에서도 강도 증가에따라 확산계수가 감소하는 경향이 파악되었다. 본 연구의 결과에서는 BFS6000 및 8000을 30 및 50% 혼입한 콘크리트의 경우 OPC 대비 동등 이상의 강도 확보는 물론 염분침투저항성을 보다 효과적으로 향상시킬 수 있을 것으로 확인되었다.
(7) 시뮬레이션에 의한 압축강도의 정량적 예측·평가 결과에서 실험을 통해 얻어진 압축강도의 실측치 대비 시뮬레이션에 의한 예측치가 낮은 것으로 나타났다. 하지만, 본 연구에서 시뮬레이션을 활용한 압축강도의 정량적 예측·평가를 위해 설정한 오차범위인 10% 이하를 만족하는 것으로 확인되었다.
(8) 시뮬레이션에 의한 확산계수의 정량적 예측·평가에서도 실험을 통해 얻어진 확산계수의 실측치 대비 시뮬레이션에 의한 예측치가 높은 것으로 나타났다. 확산계수의 실측치와 예측치의 오차 범위에서 OPC 콘크리트의 경우 1.35(×10-12m2/s), FA 또는 BFS 콘크리트는 각각 1.44 및 0.55 (×10-12m2/s)정도 시뮬레이션에 의한 예측치가 높은 것으로 확인되었다.
(9) 본 연구의 결과를 토대로 향후, FA 또는 BFS 콘크리트의 염분침투성을 단기간에 파악할 수 있는 기술개발과의 연계를 위한 기초적인 자료로서 제시하고자 한다. 나아가, 시뮬레이션에 의한 FA 또는 BFS 콘크리트의 압축강도 및 확산계수의 정량적 예측·평가를 위한 데이터베이스의 구축은 물론 현장 적용을 위한 정량적 지표로서도 적용 가능할 것으로 판단된다.

목차

Ⅰ. 서론
1.1 연구의 배경 및 목적 ···················································································· 1
1.2 콘크리트 염분침투성의 연구동향 ································································· 4
1.3 연구의 범위 및 방법 ··················································································· 8
1.4 연구의 구성 ··································································································· 9
Ⅱ. 이론적 고찰
2.1 염해(鹽害) ··································································································· 11
2.1.1 염해에 의한 철근부식 ······································································· 11
2.1.2 염화물 이온의 확산과 철근부식 ····················································· 13
2.1.3 염화물 이온의 측정방법 ··································································· 16
2.1.4 염화물 이온의 시험방법 ··································································· 18
2.2 플라이애쉬(FA) ························································································· 23
2.2.1 개요 ······································································································· 23
2.2.2 FA 성질 ······························································································· 24
2.2.3 FA 콘크리트의 특성 ········································································· 26
2.2.4 국내외 활용현황 ················································································· 27
2.3 고로슬래그미분말(BFS) ··········································································· 29
2.3.1 개요 ······································································································· 29
2.3.2 BFS 성질 ····························································································· 30
2.3.3 BFS 콘크리트의 특성 ······································································· 33
2.3.4 국내외 활용현황 ················································································· 36
Ⅲ. FA 또는 BFS 콘크리트의 역학적 특성
3.1 실험계획 ······································································································· 39
3.1.1 사용재료 ······························································································· 39
3.1.2 배합 및 양생 ······················································································· 45
3.2 실험방법 ······································································································· 47
3.2.1 경화 전의 콘크리트 실험방법 ························································· 47
3.2.2 경화 후의 콘크리트 실험방법 ························································· 48
3.3 결과 및 분석 ······························································································· 49
3.3.1 FA 또는 BFS 콘크리트의 유동성 ················································· 49
3.3.2 FA 콘크리트의 역학적 특성 ··························································· 52
3.3.3 BFS 콘크리트의 역학적 특성 ························································· 55
3.4 소결 ··············································································································· 59
Ⅳ. FA 또는 BFS 콘크리트의 염분침투저항성
4.1 본 연구에서의 염분침투시험방법 ··························································· 60
4.2 FA 또는 BFS 콘크리트의 염분침투저항성 ········································· 64
4.2.1 FA의 혼입이 확산계수에 미치는 영향 ········································· 64
4.2.2 BFS의 혼입이 확산계수에 미치는 영향 ······································· 70
4.3 역학적 특성과 확산계수의 관계 ····························································· 78
4.3.1 FA 콘크리트 ······················································································· 78
4.3.2 BFS 콘크리트 ····················································································· 80
4.4 소결 ··············································································································· 83
Ⅴ. FA 또는 BFS 콘크리트의 예측·평가
5.1 시뮬레이션을 이용한 예측·평가 ··························································· 85
5.1.1 시뮬레이션 프로그램 ········································································· 85
5.1.2 본 연구에서의 시뮬레이션 프로그램 ············································· 86
5.2 시뮬레이션에 의한 예측·평가 ······························································· 91
5.2.1 압축강도 예측·평가 ········································································· 91
5.2.2 확산계수 예측·평가 ········································································· 93
5.3 소결 ··············································································································· 95
Ⅵ. 결론 ·············································································································· 96
참고문헌
ABSTRACT

최근 본 자료

전체보기

댓글(0)

0