Abstract
In this paper, we introduce a novel approach for the targeted delivery of concentrated alkali required for activation of aluminosilicate-based cements, which avoids exposure to caustic solutions on site. The solid alkali, encapsulated within a water-soluble glass (alkali-doped carboxylate glass) is dry blended with mineral admixtures (ground granulated blast slag and fly ash) and water saturated superabsorbent polymers (SAP, being the only source of mix water in this study). The solubility of alkali-doped carboxylate glasses (ACG) was characterized. The hydration of ground granulated blast slag (GGBS) and fly ash (FA) with different curing times were monitored by SEM, XRD, FT-IR and solid-state MAS NMR, which showed the co-existence of calcium aluminum silicate hydrate (C-A-S-H) gel and sodium aluminosilicate hydrate (N-A-S-H) gel in the hydration products. The mechanical properties of AAC were tested, and the compressive strength of AAC (using ACG as alkali activator, water saturated SAP as water source) reached over 40 MPa after curing for 28 days.
Original language | English |
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Article number | 131459 |
Number of pages | 10 |
Journal | Construction and building materials |
Volume | 383 |
Early online date | 18 Apr 2023 |
DOIs | |
Publication status | Published - 20 Jun 2023 |
Bibliographical note
AcknowledgmentsWe gratefully acknowledge the financial support of China National Key R&D Program (Grant No. 2018YFE0106300) and National Nature Science Foundation of China (No: 51925205). We gratefully acknowledge the financial support of “111” project (No. B18038). We gratefully acknowledge the Dr. Helle Rüsz Hansen for her contribution to the development of the slow release glasses used in this paper.
Data Availability Statement
No data was used for the research described in the article.Keywords
- Alkali-activated cement
- Alkali-doped carboxylate glass
- Superabsorbent polymer
- SEM
- Solid-state NMR