Theoretical Modeling and Experimental Analyses of Laminated Wood Composite Poles

Authors

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

Keywords:

Beams, composites, energy methods, higher-order differential equation, poles, thick-shell, Timoshenko beam theory, variational methods

Abstract

Wood laminated composite poles consist of trapezoid-shaped wood strips bonded with synthetic resin. The thick-walled hollow poles had adequate strength and stiffness properties and were a promising substitute for solid wood poles. It was necessary to develop theoretical models to facilitate the manufacture and future installation and maintenance of this novel engineered wood product. A higher-order governing differential equation (GDE) model was developed for this purpose based on the principle of minimum potential energy. Transverse shear and glue-line effects were taken into account in the development of the model. A simplified theoretical model was also derived to further validate the higher-order GDE model. Thirty-six small-scale wood laminated composite poles were made and tested to validate the models developed. Strip thickness and number of strips were chosen as experimental variables. The deflection predicted by the theoretical models agreed well with those measured in experiment. The agreement with the results predicted by the simplified theoretical model was better than that with those predicted by the higher-order GDE model.

References

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Published

2007-06-05

Issue

Number 4 / October 2005

Section

Research Contributions

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