Summary: | Compared with solid wood, one of the advantages of wood-based
composites is the great potential for the design of material properties through
manipulation of manufacturing variables. Large strides are presently being
made in the design of non-veneer structural panels such as oriented strand
board (OSB) by using material science and engineering principles. Scientists
and engineers have been more successful in designing synthetic fiber-reinforced
composites than wood-based composites, mainly because of the
complexity of the microstructures and the inherent variability of the wood
composites. In this study, recent research in modeling and predicting the
properties of flakeboards has been summarized. The relationships among the
structure in terms of void volume, density distribution, and the properties of
the panels are discussed. With the help of a robotic system, very thin
partially oriented wood assemblies were made and tested. The relationship
between flake orientation and tensile strength and tensile MOE were
determined. The relationship between density and tensile strength and tensile
MOE were also examined. Based on layer properties, a three-layer
mathematical model was derived to predict the tensile strength and tensile
MOE. Partially oriented three-layer OSB panels were made and tested to
verify this mathematical model. Very good agreement was found between
this model and experimental results. Furthermore, a 3D finite element model
was developed to simulate the probability of failure and probabilistic
distribution of tensile strength of OSB. The probabilistic distributions of
tensile strength and the load capacity probabilistic distributions for three-layer
partially oriented OSB were predicted successfully. Good agreement
between predictions and experimental data was observed.
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