Simulation Based Modeling of the Elastic Properties of Structural Composite Lumber
Keywords:Wood composites, elastic properties, simulation modeling
Structural composite lumber (SCL) products were introduced into the construction practice several decades ago. Their apparent advantages over traditional lumber did not generate copious research interests. However, increasing demands for structural materials coupled with the decreasing quality and quantity of raw materials are forcing the industry to introduce short rotation trees or species having unfavorable properties into the manufacturing processes. Consequently, there is a need for research to further enhance the effective use of renewable natural resources.
This article describes the development of simulation models that estimate the bending and orthotropic compression modulus of elasticity (MOE) of laminated veneer lumber (LVL) and parallel strand lumber (PSL). The Monte Carlo simulation-based routines use the physical/mechanical properties of primary constituting elements, obtained from probability distributions, to calculate a particular property of the composite system. Furthermore, the orthotropic behavior of the wood constituents due to their position in the composite is modeled by well-established theoretical/empirical equations. Results and experimental validation regarding the geometric, physical, and mechanical attributes showed reasonably good agreement between simulated and experimental values. Developed models have good potential for predicting the elastic parameters of composites using new raw materials or novel design features.
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