Contributions to the study of porosity in fly ash-based geopolymers. Relationship between degree of reaction, porosity and compressive strength

The main contribution of this paper relates to the development of a systematic study involving a set of parameters which could potentially have an impact on geopolymer properties: curing temperature, type of activating solution, alkali metal in solution, incorporation of slag (Ca source) and type of...

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Detalhes bibliográficos
Autores: Luna Galiano, Yolanda, Fernández Pereira, Constantino, Izquierdo, M.
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2016
País:España
Recursos:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/69838
Acesso em linha:https://hdl.handle.net/11441/69838
https://doi.org/10.3989/mc.2016.10215
Access Level:acceso abierto
Palavra-chave:Fly ash
Blast furnace slag
Alkali-activated cement
Descrição
Resumo:The main contribution of this paper relates to the development of a systematic study involving a set of parameters which could potentially have an impact on geopolymer properties: curing temperature, type of activating solution, alkali metal in solution, incorporation of slag (Ca source) and type of slag used. The microstructures, degrees of reaction, porosities and compressive strengths of geopolymers have been evaluated. Geopolymers prepared with soluble silicate presented a more compacted and closed structure, a larger amount of gel, lower porosity and greater compressive strength than those prepared with hydroxides. On the other hand, Na-geopolymers were more porous but more resistant than K-geopolymers. Although there is an inverse relation between degree of reaction and porosity, between compressive strength and porosity it is not always inversely proportional and could, in some cases, be masked by changes produced in other influencing parameters.