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Title: Predictive Models for Elastic Bending Behavior of a Wood Composite Sandwich Panel
Strands produced from small-diameter timbers of lodgepole and ponderosa pine were used to fabricate a composite sandwich structure as a replacement for traditional building envelope materials, such as roofing. It is beneficial to develop models that are verified to predict the behavior of these sandwich structures under typical service loads. When used for building envelopes, these structural panels are subjected to bending due to wind, snow, live, and dead loads during their service life. The objective of this study was to develop a theoretical and a finite element (FE) model to evaluate the elastic bending behavior of the wood-strand composite sandwich panel with a biaxial corrugated core. The effect of shear deformation was shown to be negligible by applying two theoretical models, the Euler–Bernoulli and Timoshenko beam theories. Tensile tests were conducted to obtain the material properties as inputs into the models. Predicted bending stiffness of the sandwich panels using Euler-Bernoulli, Timoshenko, and FE models differed from the experimental results by 3.6%, 5.2%, and 6.5%, respectively. Using FE and theoretical models, a sensitivity analysis was conducted to explore the effect of change in bending stiffness due to intrinsic variation in material properties of the wood composite material.  more » « less
Award ID(s):
1150316
NSF-PAR ID:
10185060
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Forests
Volume:
11
Issue:
6
ISSN:
1999-4907
Page Range / eLocation ID:
624
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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