Study on the Characteristics of Crystal Formation and Transformation of Alkali-Activated Slag Minerals Induced by Weak Alkali

Strong-alkali activation is a prerequisite needed to ensure the full polymerization activity of alkali slag binder and establish excellent mechanical properties; however, it substantially increases the preparation cost. In this study, the effects of both strong and weak alkaline activators on the ac...

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Main Authors: Guodong Huang, Yonghao Huang, Xiaojun Zheng, Fengan Zhang, Jiahao Xu, Jun Qi, Zijian Chen
Format: Article
Language:English
Published: MDPI AG 2024-12-01
Series:Crystals
Subjects:
Online Access:https://www.mdpi.com/2073-4352/14/12/1086
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author Guodong Huang
Yonghao Huang
Xiaojun Zheng
Fengan Zhang
Jiahao Xu
Jun Qi
Zijian Chen
author_facet Guodong Huang
Yonghao Huang
Xiaojun Zheng
Fengan Zhang
Jiahao Xu
Jun Qi
Zijian Chen
author_sort Guodong Huang
collection DOAJ
description Strong-alkali activation is a prerequisite needed to ensure the full polymerization activity of alkali slag binder and establish excellent mechanical properties; however, it substantially increases the preparation cost. In this study, the effects of both strong and weak alkaline activators on the activation performance of alkali slag were examined, using a combination of X-ray diffraction, scanning electron microscopy, and Fourier-transform infrared spectroscopy analysis methods. The reaction mechanism was analyzed under different alkaline conditions, and the preparation cost could be significantly reduced without significantly degrading mechanical properties. The results indicate that Ca(OH)<sub>2</sub> can stimulate the reactivity of slag, resulting in a 40% decrease in compressive strength (compared to NaOH) but a 25–50% reduction in preparation cost. With increasing Ca(OH)<sub>2</sub> dosage, the compressive strength first increases and then decreases. The best excitation effect is achieved at a dosage of 40 g Ca(OH)<sub>2</sub> per 450 g GBFS. The formation of aluminosilicate is the main driving force for the observed increase in compressive strength. Excessive dosage of Ca(OH)<sub>2</sub> will lead to its deposition in the specimen, thus affecting the development of compressive strength.
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institution Kabale University
issn 2073-4352
language English
publishDate 2024-12-01
publisher MDPI AG
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series Crystals
spelling doaj-art-94f2de30420e4ffa87a5b82a9807d1b42024-12-27T14:19:51ZengMDPI AGCrystals2073-43522024-12-011412108610.3390/cryst14121086Study on the Characteristics of Crystal Formation and Transformation of Alkali-Activated Slag Minerals Induced by Weak AlkaliGuodong Huang0Yonghao Huang1Xiaojun Zheng2Fengan Zhang3Jiahao Xu4Jun Qi5Zijian Chen6School of Civil Engineering and Construction, Anhui University of Science and Technology, Huainan 232001, ChinaSchool of Civil Engineering and Construction, Anhui University of Science and Technology, Huainan 232001, ChinaChina Construction Second Engineering Bureau Co., Ltd., Beijing 100160, ChinaSpecial Equipment Inspection Institute of Anhui, Hefei 230051, ChinaSchool of Civil Engineering and Construction, Anhui University of Science and Technology, Huainan 232001, ChinaSchool of Civil Engineering and Construction, Anhui University of Science and Technology, Huainan 232001, ChinaSchool of Civil Engineering and Construction, Anhui University of Science and Technology, Huainan 232001, ChinaStrong-alkali activation is a prerequisite needed to ensure the full polymerization activity of alkali slag binder and establish excellent mechanical properties; however, it substantially increases the preparation cost. In this study, the effects of both strong and weak alkaline activators on the activation performance of alkali slag were examined, using a combination of X-ray diffraction, scanning electron microscopy, and Fourier-transform infrared spectroscopy analysis methods. The reaction mechanism was analyzed under different alkaline conditions, and the preparation cost could be significantly reduced without significantly degrading mechanical properties. The results indicate that Ca(OH)<sub>2</sub> can stimulate the reactivity of slag, resulting in a 40% decrease in compressive strength (compared to NaOH) but a 25–50% reduction in preparation cost. With increasing Ca(OH)<sub>2</sub> dosage, the compressive strength first increases and then decreases. The best excitation effect is achieved at a dosage of 40 g Ca(OH)<sub>2</sub> per 450 g GBFS. The formation of aluminosilicate is the main driving force for the observed increase in compressive strength. Excessive dosage of Ca(OH)<sub>2</sub> will lead to its deposition in the specimen, thus affecting the development of compressive strength.https://www.mdpi.com/2073-4352/14/12/1086alkaline activationgranulated blast furnace slagcompressive strengthactivatorCa(OH)<sub>2</sub>
spellingShingle Guodong Huang
Yonghao Huang
Xiaojun Zheng
Fengan Zhang
Jiahao Xu
Jun Qi
Zijian Chen
Study on the Characteristics of Crystal Formation and Transformation of Alkali-Activated Slag Minerals Induced by Weak Alkali
Crystals
alkaline activation
granulated blast furnace slag
compressive strength
activator
Ca(OH)<sub>2</sub>
title Study on the Characteristics of Crystal Formation and Transformation of Alkali-Activated Slag Minerals Induced by Weak Alkali
title_full Study on the Characteristics of Crystal Formation and Transformation of Alkali-Activated Slag Minerals Induced by Weak Alkali
title_fullStr Study on the Characteristics of Crystal Formation and Transformation of Alkali-Activated Slag Minerals Induced by Weak Alkali
title_full_unstemmed Study on the Characteristics of Crystal Formation and Transformation of Alkali-Activated Slag Minerals Induced by Weak Alkali
title_short Study on the Characteristics of Crystal Formation and Transformation of Alkali-Activated Slag Minerals Induced by Weak Alkali
title_sort study on the characteristics of crystal formation and transformation of alkali activated slag minerals induced by weak alkali
topic alkaline activation
granulated blast furnace slag
compressive strength
activator
Ca(OH)<sub>2</sub>
url https://www.mdpi.com/2073-4352/14/12/1086
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