Investigation of OSB Thickness-Swell Based on a 3-D Density Distribution. Part II. Variations in Thickness-Swell and Internal Stresses


  • Alan D. Tackie
  • Siqun Wang
  • Richard M. Bennett


Thickness-swell, oriented strandboard, modeling, density distribution, resin content, finite element


A recently developed finite element (FE) model was used to examine the thickness-swell, density changes, and internal stresses in oriented strandboard (OSB) panels under moisture loading. The model accounts for the nonlinear mechanical behavior of OSB and for the moisture transport through the specimen. The FE model is based on the 3-D density variation of the board. The density variation, resulting from manufacturing processes, affects the uniformity of thickness-swell in OSB and is often exacerbated by continuous sorption of moisture, which leads to potentially damaging internal stresses in the panel. The model was validated through comparison of experimental results. The use of the model is illustrated by quantifying the effects of resin content changes on thickness swell, and the examination of internal stresses and bond failures in an OSB specimen.


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Research Contributions