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BIBTEX RIS

Geopolimeros com base em cinzas volantes activadas com naoh y Ca(OH)2: caracterização microestrutural por rmn-mas 29Si y 27Al

2016; National Training Service (Colombia); Volume: 80; Issue: 2 Linguagem: Inglês

10.23850/22565035.487

ISSN

2256-5035

Autores

Jherson Eveiro Díaz Rosero, Alexandre Silva de Vargas, Denise Carpena Coitinho Dal Molin, Ângela Borges Masuero, Rosane Aguiar da Silva San Gil, Ruby Mejía de Gutiérrez,

Tópico(s)

Recycling and utilization of industrial and municipal waste in materials production

Resumo

In fly-ash alkali-activation technology, depending on the combination of activators, deleterious reactions may result in a drop in resistance with age. This Studiy aimed to evaluate the compressive strength of alkali-activated fly ash from combined solutions of NaOH and Ca(OH)2. Three molar ratio CaO/SiO2 (C/S) were studied: 0.05 (M5), 0.15 (M15) e 0.25 (M25). Resistances order of 21 MPa (M15) and 19 MPa (M25) were reached at the age of 7 days. However, after 28 and 91 days, the resistances were 8 MPa and 7 MPa, respectively. The M5 samples showed rising behavior of resistance with age. Thus, the drop in resistance has conditioned the C/S matrices. In the 29Si NMR spectra of the M25 sample Si has decreased species Q4 (3Al) and Q4 (2Al), those responsible for the mechanical properties of activated samples.

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