Mechanical Properties of Small-Scale Wood Laminated Composite Poles
Keywords:Composite poles, wood composites, LCP, shear strength, crushing strength, utility poles
AbstractPower companies in the United States consume millions of solid wood poles every year. These poles are from high-valued trees that are becoming more expensive and less available. Wood laminated composite poles (LCP) are a novel alternative to solid wood poles. LCP consist of trapezoid wood strips that are bonded by a synthetic resin. The wood strips can be made from low-valued wood and residues. This study evaluated the mechanical performance of small-scale LCP as affected by strip thickness and number of strips in a pole. The maximum bending stress of composite poles was comparable to that of solid poles of the same sizes. Thicker wood strips lead to stronger glue-line shear but poorer crushing stress. Number of strips in a pole was positively correlated to modulus of elasticity (MOE) and shear stress but negatively correlated to crushing stress. The results suggest that LCP with shell thickness greater than 50% of its diameter could be a possible substitute for solid wood poles. Thinner shells can be used by filling partially or totally the hallow core with other materials such as processing wastes.
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