Study of the rheological and microstructural properties of a geopolymer binder based on fly ash

Geopolymers are a potential alternative substitute for Portland cement binders in some applications. However, there are many unexplored research topics to be conducted on this subject. Thus, this study aimed to investigate the rheological and mechanical properties of geopolymer pastes based on Class...

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Detalles Bibliográficos
Autores: Araújo, Lucas Benício Rodrigues, Bezerra, Ana Karoliny Lemos, Silva, Leonária Araújo, Chaves, Andressa Cristina Borges, Costa, Heloina Nogueira da, Babadopulos, Lucas Feitosa de Albuquerque Lima
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2023
País:Brasil
Institución:Associação Nacional de Tecnologia do Ambiente Construído (ANTAC)
Repositorio:Ambiente construído (Online)
Idioma:portugués
OAI Identifier:oai:seer.ufrgs.br:article/126070
Acceso en línea:https://seer.ufrgs.br/index.php/ambienteconstruido/article/view/126070
Access Level:acceso abierto
Palabra clave:geopolymer
fly ash
rheology
microstructure
geopolímero
cinza volante
reologia
microestrutura
Descripción
Sumario:Geopolymers are a potential alternative substitute for Portland cement binders in some applications. However, there are many unexplored research topics to be conducted on this subject. Thus, this study aimed to investigate the rheological and mechanical properties of geopolymer pastes based on Class F fly ash activated by a solution of NaOH and Na2SiO3, with activator/precursor ratios of 0.5, 0.6 and 0.7, by mass. Furthermore, microstructural and chemical analyses. Rheological properties were determined from flow tests with shear rates between 0 s-1 and 100 s-1 at 25°C. Mechanical analysis was performed from simple compressive strength tests on the hardened pastes. The results of simple compression indicated better strength values for lower activator/precursor ratios. In flow tests, the material behaved as a pseudoplastic fluid, and, with the increase of the activator/precursor ratio, there was a reduction of apparent viscosity values. Therefore, by evaluating the mechanical and rheological results, it was noticed that the paste that presented the best properties was the one with activator/precursor ratio 0.6.