• 한국세라믹학회지
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• 제11권1호
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• pp.10-18
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• 1974

The hydration at $23^{\circ}C$ between $Ca(OH)_2$ and siliceous materials with various compositions of silica gel and quartz were studied in paste state, and also diatomite was empolyed as another form of silica. The effect of the structural state of silica on the pozzolanic reactivity was investigated by X-ray, DTA, electron microscopy, and chemical analysis. The results obtained were as follows. (1) The molar ratio of $Ca(OH)_2$ to silica gel(C/Sg) being changed in 0.49, 0.81 and 1.22, the free $Ca(OH)_2$ was disappeared within six hours, three days and two weeks respectively and ill-crystallized CSH(I) was formed. However, in the case fo molar ratio of C/Sg=2.45, almost lime was remained uncombinedly after twenty four weeks yet. (2) Though the molar ratio C/Sg of diatomite was 0.71, the hydration was stabilized at three weeks and the result exhibited very peculiar characteristics from silica gel. (3) Pozzolanic reactivity of quartz was negligible, but $\alpha$-cristobalite in diatomite showed appreciable reactivity. (4) The thermal curves showed the exothermic peaks in the range 830 to $930^{\circ}C$ and lower broad peaks at high temperature in the initial steps of hydration, transfered to lower temperature with sharp peaks by proceeding of hydration. (5) The samples containing more silica gel exhibited higher pozzolanic reactivity and martar strength, but the diatomite gave remarkable result for them and they were matched to the strength development rate.

• 자원리싸이클링
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• 제16권2호
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• pp.40-47
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• 2007

생활폐기물 소각장에서 발생되는 바닥재를 콘크리트 잔골재로 재활용하기 위해서, 기준모르타르에 모래 10%를 바닥재로 대체 하고 시멘트 10%를 포졸란성 규조토로 대체한 후, KS L 5105와 TCLP에 따라 시험하였다. 결과에 의하면, 바닥재의 유해중금속들은 TCLP 허용치 범위에 있었다. 포졸란성 규조토와 바닥재를 혼합한 모르타르 압축강도는 기준모르타르보다 높았으며 동시에 모든 유해중금속들은 TCLP 기준치 범위에 들어 있었다. 따라서 포졸란성 규조토를 안정재로 사용하게 되면 바닥재를 콘크리트 잔골재로 재활용할 수 있다.