Hygro-mechanical analysis of wood subjected to constant mechanical load and varying relative humidity
-
Sabina Huč
,
Staffan Svensson
Abstract
A hygro-mechanical (H-M) analysis of a wooden specimen sustaining a mechanical load while subjected to varying relative humidity was performed to predict the long-term rheological behavior of wood. The numerical analysis was based on the experimental results of total strains, monitored in two orthotropic material directions on oak wood specimens under constant uniaxial compression and with moisture content (MC) variation. For the moisture analysis, a multi-Fickian moisture transport model (MFMTM) was used to obtain temporal and spatial MC fields, which were the input data in the mechanical analysis. The presented mechanical model assumed a decomposition of the total strains into the elastic, viscoelastic and mechanosorptive strains and the strains due to shrinkage and swelling. The moisture and mechanical analyses required material parameters, which were taken from the literature or were empirically obtained by a fitting procedure. The performed H-M analysis gave accurate numerical predictions of the experimentally obtained total strains in two orthotropic directions simultaneously. Thus, the analysis developed has a high potential for predicting the long-term rheological behavior of timber structures, assuming that the material parameters are determined previously, based on specific, extensive, multidimensional experimental analyses.
Acknowledgments
The authors would like to thank their colleagues at Division of Applied Mechanics, Ångström Laboratory, Uppsala University for sharing the experimental results. The financial support by Gunnar Ivarson’s Foundation (Gunnar Ivarsons Stiftelse för Hållbart Samhällsbyggande, GIS) made this work possible.
Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
Research funding: The work of Tomaž Hozjan was supported by the Slovenian Research Agency through the research core funding, funder id: 10.13039/501100004329, No. P2-0260. The support is gratefully acknowledged.
Employment or leadership: None declared.
Honorarium: None declared.
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©2018 Walter de Gruyter GmbH, Berlin/Boston
Artikel in diesem Heft
- Frontmatter
- Original Articles
- Increasing pulp yield in kraft cooking of softwoods by high initial effective alkali concentration (HIEAC) during impregnation leading to decreasing secondary peeling of cellulose
- Effects of wet-pressing induced fiber hornification on hydrogen bonds of cellulose and on properties of eucalyptus paper sheets
- Antisolvent precipitation of hemicelluloses, lignosulfonates and their complexes from ultrafiltrated spent sulfite liquor (SSL)
- Simultaneous pyrolysis and trimethylsilylation with N-methyl-(trimethylsilyl) trifluoroacetamide for the characterisation of lignocellulosic materials from kraft pulping
- Hygro-mechanical analysis of wood subjected to constant mechanical load and varying relative humidity
- In-situ density estimation by four nondestructive techniques on Norway spruce from built-in wood structures
- Formability of wood veneers: a parametric approach for understanding some manufacturing issues
- Influence of grain direction on the time-dependent behavior of wood analyzed by a 3D rheological model. A mathematical consideration
- Isolation of secondary metabolites from Stenochlaena palustris stems and structure-activity relationships of 20-hydroxyecdysone derivatives on antitermite activity
- Effects of white rot and brown rot decay on the drilling resistance measurements in wood
Artikel in diesem Heft
- Frontmatter
- Original Articles
- Increasing pulp yield in kraft cooking of softwoods by high initial effective alkali concentration (HIEAC) during impregnation leading to decreasing secondary peeling of cellulose
- Effects of wet-pressing induced fiber hornification on hydrogen bonds of cellulose and on properties of eucalyptus paper sheets
- Antisolvent precipitation of hemicelluloses, lignosulfonates and their complexes from ultrafiltrated spent sulfite liquor (SSL)
- Simultaneous pyrolysis and trimethylsilylation with N-methyl-(trimethylsilyl) trifluoroacetamide for the characterisation of lignocellulosic materials from kraft pulping
- Hygro-mechanical analysis of wood subjected to constant mechanical load and varying relative humidity
- In-situ density estimation by four nondestructive techniques on Norway spruce from built-in wood structures
- Formability of wood veneers: a parametric approach for understanding some manufacturing issues
- Influence of grain direction on the time-dependent behavior of wood analyzed by a 3D rheological model. A mathematical consideration
- Isolation of secondary metabolites from Stenochlaena palustris stems and structure-activity relationships of 20-hydroxyecdysone derivatives on antitermite activity
- Effects of white rot and brown rot decay on the drilling resistance measurements in wood
