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미세 강섬유의 구속력이 모르타르의 알칼리-실리카 반응에 미치는 영향

Effect of Mechanical Restraint due to Steel Microfibers on Alkali-Silica Reaction in Mortars

  • 이종구 (고려대학교 건축사회환경공학과)
  • Yi, Chong-Ku (Dept. of Civil Environmental and Architectural Engineering, Korea University)
  • 발행 : 2007.10.31

초록

Steel microfiber (SMF)가 알칼리-실리카 반응 (ASR)에 미치는 영향을 두 가지 종류 (부순 오팔과 직경이 일정한 pyrex 막대)의 반응 골재를 사용하여 알아보았다. ASR에 의한 균열은 기준 모르타르에서 쉽게 발견되었으나 SMF 모르타르의 균열은 아주 제한적이었다. SMF의 균열 진전 제어 메커니즘을 통하여 ASR에 의한 모르타르의 강도 저하와 팽창을 효과적으로 막을 수 있었고, ASR 생성물들의 유동성이 저하됨을 알 수 있었다. ASR 생성물의 성분을 microprobe 분석과 ICP 분광계를 이용하여 알아보았다. SMF의 구속 효과는 액체상태인 ASR 생성물의 높은 나트륨이 온과 규소이온의 농도를 초래하였으며, 높은 이온의 농도는 ASR 알칼리-실리카 반응성을 저하하는 원인으로 생각되어 진다.

The effect of steel microfibers (SMF) on alkali-silica reaction (ASR) was investigated using two types of reactive aggregates, crushed opal and a pyrex rod of constant diameter. Cracks are less visible in the SMF mortars compared with the unreinforced mortars. Due to crack growth resistance behavior in SMF mortar specimens, the strength loss is eliminated and the ASR products remained well confined within the ASR site. The expansion and the ASR products were characterized by microprobe analysis and inductively coupled plasma (ICP) spectroscopy. The confinement due to SMF resulted in a higher Na and Si ion concentration of the ASR liquid extracted from the reaction site. The higher concentration reduced the ASR rate and resulted in a lower reactivity of the reactive pyrex rods in SMF mortars.

키워드

참고문헌

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