• Title/Summary/Keyword: CoS

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Properties of Cement Paste Containing High Volume γ-C2S and MgO Subjected to CO2 Curing (γ-C2S 및 MgO를 다량 혼입한 시멘트 페이스트의 CO2 양생유무에 따른 특성변화)

  • Sung, Myung-Jin;Cho, Hyeong-Kyu;Lee, Han-Seung
    • Journal of the Korea Institute of Building Construction
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    • v.15 no.3
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    • pp.281-289
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    • 2015

  • Carbonation of concrete causes reduction of pH and subsequently causes steel corrosion for reinforced concrete structure. However, for plain concrete structure or PC product, it can lead to a decrease in porosity, high density, improvement of concrete, shrinkage-compensation. Recently, based on this theory, research of $CO_2$ curing effect has been performed, but it was mainly focused on its effects on compressive strength using only ordinary portland cement. Researches on $CO_2$ curing effect for concrete containing $CO_2$ reactive materials such as ${\gamma}-C_2S$, MgO haven't been investigated. Therefore, this study has performed experiments under water-binder ratio 40%, and the replacement ratios of ${\gamma}-C_2S$ and MgO were 90%. Micro-chemical analysis, measurement of compressive strength according to admixtures and $CO_2$ curing were investigated. Results from this study revealed that higher strength was measured in case of $CO_2$ curing compared with none $CO_2$ curing for plain specimen indicating difference between 1.08 and 1.26 times, in case of ${\gamma}-C_2S$ 90, MgO 90 specimen, incorporating high volume replaced as much as 90%, it was proven that when applying $CO_2$ curing, higher strength which has difference between 14.56 and 45.7 times, and between 6.5 and 10.37 times was measured for each specimen compared to none $CO_2$ curing. Through micro-chemical analysis, massive amount of $CaCO_3$, $MgCO_3$ and decrease of porosity were appeared.

  • https://doi.org/10.5345/JKIBC.2015.15.3.281 인용 PDF KSCI