2014, Volume 16, Issue 4
Strategic Study of CAE >> 2014, Volume 16, Issue 4
Investigation of tangential strain caused by shrinkage anisotropy using image analytical method
College of Material Science and Engineering, Northeast Forestry University, Harbin 150040, China
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Abstract
This study investigated the image analytical method which was used to measure the tangential strains, including practical shrinkage strain, free shrinkage strain, elastic strain,viscoelastic creep strain, and mechano-sorptive (MS) creep, which caused by shrinkage anisotropy during slow conventional drying of wood disks. Also we analyzed the stress in different moisture content (MC) and the relations between stress and strain. The results showed that the image analytical method could meet the requirements in accurate level; below the fiber saturation point (FSP), the wood disks were initially subject to tangential tensile stress; with the decreasing MC, the tensile stress turned into compressive stress. The relations between stress and strain were complex. It had no obviously corresponding connections with the viscoelastic creep strain, and it was almost corresponding with the MS creep.
Keywords
image analytical method ; wood disks ; shrinkage anisotropy ; drying stress ; tangential strain
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References
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