Delayed setting time for alkali-activated slag composites using activator containing SiO2 and Na2O

• Autorzy: Hung Chi-Che , Lin Wei-Ting , Yeih Wei-Chung , Chang Jiang-Jhy

Identyfikatory

DOI

10.2478/msp-2021-0045

• Języki publikacji: EN

Abstrakty

EN

This study examines the influence of SiO₂ and Na₂O mix proportions on the properties of alkali-activated slag (AAS) pastes. In order to solve the rapid setting problem associated with AAS, phosphoric or silicic acid is commonly added to the alkaline activator. The retarding effect of these additions suggests a close relationship between pH and setting time. In this study, AAS pastes with various SiO₂ and Na₂O dosages were analyzed. Regression analysis was carried out using pH value and setting time to identify the main parameters affecting the setting time. Results showed that the alkali modulus (i.e., the weight ratio of SiO₂ over Na₂O) is correlated with the pH value. Specifically, the initial and final setting times were significantly reduced under lower SiO₂ and Na₂O dosages. Therefore, a higher alkali modulus prolonged the setting time.

Słowa kluczowe

EN

alkali activated materials; setting time; silicate-based activator; microstructure

• Wydawca: De Gruyter
• Czasopismo: Materials Science Poland
• Rocznik: 2021
• Tom: Vol. 39, No. 4
• Strony: 570--579
• Opis fizyczny: Bibliogr. 38 poz., rys., tab.

Twórcy

autor

Hung Chi-Che

• Institute of Nuclear Energy Research, Atomic Energy Council, Taoyuan 325, Taiwan

autor

Lin Wei-Ting

• Department of Civil Engineering, National Ilan University, Yilan 260, Taiwan

autor

Yeih Wei-Chung

• Department of Harbor and River Engineering, National Taiwan Ocean University, Keelung 202, Taiwan

autor

Chang Jiang-Jhy

• Department of Harbor and River Engineering, National Taiwan Ocean University, Keelung 202, Taiwan

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