Probing of wood-cement interactions during hydration of wood-cement composites by proton low-field NMR relaxometry
SÈBE, Gilles
Laboratoire de Chimie des Polymères Organiques [LCPO]
Team 2 LCPO : Biopolymers & Bio-sourced Polymers
< Réduire
Laboratoire de Chimie des Polymères Organiques [LCPO]
Team 2 LCPO : Biopolymers & Bio-sourced Polymers
Langue
en
Article de revue
Ce document a été publié dans
Journal of Materials Science. 2011, vol. 46, n° 5, p. 1167-1175
Springer Verlag
Résumé en anglais
Proton NMR T (2) relaxometry has been applied to investigate phenomena involved in wood-cement composites during hydration. The transformation of capillary pore water into hydrates and gel pore water, as well as the ...Lire la suite >
Proton NMR T (2) relaxometry has been applied to investigate phenomena involved in wood-cement composites during hydration. The transformation of capillary pore water into hydrates and gel pore water, as well as the microstructural changes occurring in the cement matrix, was continuously monitored during the first 28 days of hydration. Water in wood and its transfer into the matrix as cement hardens were also evidenced with the method. It has been found, for example, that some of the water in the mixture is retained in wood in the form of bound or free water, depending on the initial water content. By measuring the area under the different peaks, the consumption of water during hydration can be measured and the advancement of the hydration process can be evaluated via the hydration advancement coefficient alpha. The cement hardening within the composite has been also studied in the presence of calcium chloride, an accelerating agent. The acceleration was clearly evidenced at the early stage of the hydration process. The influence of extractives has been evaluated by comparing the hydration behaviour of composites prepared from Eucalyptus saligna (low extractives content) and Afzelia bipendensis (high extractives content), and a new compatibility index based on NMR relaxometry measurements has been proposed.< Réduire
Mots clés en anglais
CONCRETE
ORDINARY PORTLAND-CEMENT
SPIN-SPIN RELAXATION
COMPRESSIVE STRENGTH
MOISTURE-CONTENT
WATER
COMPATIBILITY
PASTES
MICROSTRUCTURE
FIBERS
Origine
Importé de halUnités de recherche