Preliminary Reactivity Test for Precursors of Alkali-Activated Materials
نویسندگان
چکیده
Alkali-activated materials (AAMs) result from the dissolution process and polycondensation of precursors in high pH solutions. This material is considered alternative cement with similar properties lower environmental impact than Portland cement. However, AAMs are subjected to same standardization applied cement-based since no formal methods exist characterize this and/or precursor reactivity. Therefore, work aims develop a method reactivity main used produce AAMs. Hence, were assessed two steps after chemical, physical, mineralogical characterization. The first step evaluated crystallinity change acid attack by mixing 1 g each 100 mL 1% HF solution for 6 h at ambient temperature. was comparing X-ray diffraction before attack. second involved evaluating formation geopolymerization products pastes studied through FTIR test. produced Na2SiO3 NaOH as activators. After 28 days curing, submitted test structural analysis. tested traditional alkali activation (i.e., silica fume (SF), blast furnace slag (BFS), metakaolin (MK)), addition sugarcane bagasse ash mechanically treated (SCBAM) heat (SCBAMH) SCBA promising activation. Considering (step 01), 02), chemical composition (preliminary characterization), it could be concluded that: (i) surface area not relevant small particle size (<23 µm); (ii) amorphous only if exhibits optimal composition; (iii) crucial parameter In addition, potential should have significant halo SiO2/Al2O3 ratio 2 5. Also, that SF SCBAMH do exhibit adequate while BFS, MK, SCBAM can classified reactive precursors.
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ژورنال
عنوان ژورنال: Buildings
سال: 2023
ISSN: ['2075-5309']
DOI: https://doi.org/10.3390/buildings13030693