Porous Structure of ultra-high-performance fibre-reinforced concretes

The aim of this experimental work was to study the porous structure of Ultra-High- Performance Fibre-Reinforced Concretes (UH) made with different fibre volume contents (0%, 1%, 2%) under several curing conditions (laboratory environment, 20 °C, 60 °C, 90 °C), comparing the results with those rec...

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Detalles Bibliográficos
Autores: Valcuende Payá, Manuel Octavio, Lliso Ferrando, Josep Ramon, Roig Flores, Marta, Gandía Romero, José Manuel
Tipo de recurso: artículo
Fecha de publicación:2021
País:España
Institución:Consejo General de la Arquitectura Técnica de España (CGATE)
Repositorio:RIARTE
OAI Identifier:oai:www.riarte.es:20.500.12251/2634
Acceso en línea:http://hdl.handle.net/20.500.12251/2634
https://www.scopus.com/inward/record.uri?eid=2-s2.0-85103394817&doi=10.3390%2fma14071637&partnerID=40&md5=54d54d530ba8b26be953a642e43eaea7
Access Level:acceso abierto
Palabra clave:Hormigón estructural (HE)
Fibra de refuerzo
Material compuesto
Hormigón de Alta Resistencia
Porosidad
Ensayos (propiedades o materiales)
Resistencia mecánica
Material de construcción
3305.05 Tecnología del Hormigón
2211.02 Materiales Compuestos
3305.33 Resistencia de Estructuras
3313.04 Material de Construcción
3312.09 Resistencia de Materiales
3312.08 Propiedades de Los Materiales
3312.12 Ensayo de Materiales
Descripción
Sumario:The aim of this experimental work was to study the porous structure of Ultra-High- Performance Fibre-Reinforced Concretes (UH) made with different fibre volume contents (0%, 1%, 2%) under several curing conditions (laboratory environment, 20 °C, 60 °C, 90 °C), comparing the results with those recorded for ordinary, high strength and very high strength concretes. Scanning electron microscopy, mercury intrusion porosimetry, thermogravimetry, water absorption and oxygen permeability tests were carried out. The results showed a low portlandite content in UH (in the order of 75% lower than in concrete C50) and a low degree of hydration, but they rise with curing temperature. These concretes have a very fine porous structure, with a high concentration of pores on the nanoscale level, below 0.05 µm. Their porosity accessible to water is consequently around 7-fold lower than in conventional (C30), 6-fold lower than in high-strength (C50) and 4- fold lower than in very high-strength (C90) concretes. Their oxygen permeability is at least one order of magnitude lower than in C90, two orders of magnitude lower than in C50 and three orders of magnitude lower than in C30. The percentage of added steel fibre does not affect the UH porous structure. © 2021 by the authors.