Abstract
The effects of variation in humidity coupled with long-term loading give rise to dimensional changes and creep effects in wooden elements. Many wooden products such as cross-laminated timber (CLT) plates as well as many common structural details used in timber engineering are vulnerable to variations in moisture content (MC) as well as to creep effects. This paper addresses the long-term effects in the material modelling of timber by the finite element method (FEM), also considering the viscoelastic and mechanosorptive effects in wood. The model was calibrated using both relaxation tests and creep tests. The results from both long-term compression perpendicular- to-grain tests (relaxation and creep) performed on glulam (GL30c) from Norway spruce (Picea abies) with moisture control are presented in this paper. The material model considers the effect of loading and moisture changes. For realistic comparison, the pith location of each lamella was specified in the numerical analyses. Ultimately, a comparison between the numerical results and the experimental results has been provided, exhibiting an overall good estimation of timber response.
Author contributions: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
Research funding: This study was funded by the WoodWisdom-Net+ project DuraTB (“Durable Timber Bridges”). The support from the funding bodies and partners is gratefully acknowledged.
Employment or leadership: None declared.
Honorarium: None declared.
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Supplementary Material
The online version of this article offers supplementary material (https://doi.org/10.1515/hf-2018-0218).
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Articles in the same Issue
- Frontmatter
- Original Articles
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- Modelling the viscoelastic mechanosorptive behaviour of Norway spruce under long-term compression perpendicular to the grain
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Articles in the same Issue
- Frontmatter
- Original Articles
- Influence of tree height on the hydrophilic and lipophilic composition of bark extracts from Eucalyptus globulus and Eucalyptus nitens
- Modelling the viscoelastic mechanosorptive behaviour of Norway spruce under long-term compression perpendicular to the grain
- Frequency-dependent viscoelastic properties of Chinese fir (Cunninghamia lanceolata) under hygrothermal conditions. Part 1: moisture adsorption
- Frequency-dependent viscoelastic properties of Chinese fir (Cunninghamia lanceolata) under hygrothermal conditions. Part 2: moisture desorption
- Evolution of extractive composition in thermally modified Scots pine during artificial weathering
- Dynamic mechanical analysis (DMA) at room temperature of archaeological wood treated with various consolidants
- Visual and machine strength grading of European ash and maple for glulam application
- Evaluation of bond strength of cross-laminated LSL specimens under short-span bending