KATKILARIN ÇİMENTO HAMURU HİDRATASYON ISISINA ETKİLERİ

Bu çalışmada, Trisodyum sitrat (C6H5Na3O7 – Ret. 1), sitrik asit (C6H8O7 – Ret.2) ve tartarik asit (C4H6O6 – Ret.3)çimento harçlarının hidratasyon süreçlerini geciktirmek amacıyla kullanılmıştır. Katkılar Portland çimentosununhidratasyon ısısı üzerine etkileri ele alınarak incelenmiştir. Hidratasyon süreçleri boyunca karışımların ısı çıkışıgrafikleri izotermal kalorimetre kullanılarak çizilmiştir. Karışımların ısı çıkışları katkıların hızlı çözünmeözelliklerine bağlı olarak değişirler. Katkısız çimento hamuru bütün karışımlar arasında en erken priz süresinesahiptir. Kalorimetre grafikleri katkı oranı arttıkça priz süresinin uzadığını işaret eder. 0.2 % oranında, tartarik asitgeciktirme üzerinden güçlü etkiye sahiptir.

Anahtar Kelimeler:

Hidratasyon ısısı, Organik katkılar, İzotermal kalorimetre

EFFECTS OF ADMIXTURES ON HYDRATION HEAT OF CEMENT PASTE

In this study, Trisodium citrate (C6H5Na3O7 – Ret. 1), citric acid (C6H8O7 – Ret.2) and tartaric acid (C4H6O6 – Ret.3)were used to retard the hydration process of cement paste. Admixtures were investigated with respect to their effectson the hydration heat of ordinary Portland cement. Heat liberation graphs of mixes during hydration process wereplotted by using isothermal calorimetry. Heat liberation of mixes varies due to their different rapid dissolutionproperties. Cement paste without a retarder has an early setting time between all mixes. The calorimetric graphsindicate that the setting time increases as the ratio of retarder increases. At the ratio of 0.2 %, tartaric acid has thestrongest effect on retardation.

Keywords:

Hydration heat, Organic admixtures, Isothermal calorimetry,

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