Mechanical Properties of Small-Scale Wood Laminated Composite Poles

Authors

  • Cheng Piao
  • Todd F. Shupe
  • Chung Y. Hse

Keywords:

Composite poles, wood composites, LCP, shear strength, crushing strength, utility poles

Abstract

Power 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.

References

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Published

2007-06-05

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Section

Research Contributions