Mechanisms of liquid transport in softwood inferred from Magnetic Resonance Imaging

Dang-Mao Nguyen (1) , Sabine Caré (2, 1) , Denis Courtier-Murias (1) , Philippe Coussot (1)

1 navier umr 8205 - Laboratoire Navier
2 msa - Matériaux et Structures Architecturés

Water in wood material plays a major role with regard to its mechanical or physical properties in various situations, in particular in outdoor applications, leading to a possible deterioration in the performance of the wood elements (eg. structural integrity, thermal insulation). Therefore, it is crucial to understand the water uptake and release as well how the water transports in the wood material to extend the lifetime of the timber buildings. The mechanisms of liquid transport are related to the hierarchical and multi-scale structure of wood and to the presence of free and bound water. Despite numerous studies, the water migration process in wood material is not well understood. For this study, softwood materials used in construction are subjected to imbibition tests. Through an original approach coupling quantitative information obtained from mass and deformation measurements, Nuclear Magnetic Resonance (NMR) and Magnetic Resonance Imaging, we are able to quantify bound and free water, which finally allows to better understand imbibition mechanisms. Additional experiments with oil (dodecane) allow to compare the characteristics of water imbibition with those of a liquid not hygroscopically adsorbed in wood.

Mots clés: Imbibition; MRI; Oil; Softwood; Sorption; Douglas-fir

Domaines: Mécanique des matériaux [physics.class-ph]

Dang-Mao Nguyen, Sabine Caré, Denis Courtier-Murias, Philippe Coussot. Mechanisms of liquid transport in softwood inferred from Magnetic Resonance Imaging. 7èmes journées du GDR 3544 « Sciences du bois », Nov 2018, Cluny, France. 4p. ⟨hal-01986129⟩