Finite Element Modeling of Small-Scale Tapered Wood-Laminated Composite Poles with Biomimicry Features<sup>1</sup>

Authors

  • Cheng Piao
  • Todd F. Shupe
  • R. C. Tang
  • Chung Y. Hse

Keywords:

Biomimicking, composite poles, finite element analysis, shear stress, taper

Abstract

Tapered composite poles with biomimicry features as in bamboo are a new generation of wood laminated composite poles that may some day be considered as an alternative to solid wood poles that are widely used in the transmission and telecommunication fields. Five finite element models were developed with ANSYS to predict and assess the performance of five types of composites members: a tapered hollow pole with webs (Pole-A), a tapered hollow pole without webs (Pole-B), a tapered solid composite pole (Pole-C), a uniform-diameter hollow pole with webs (Pole-D), and a uniform-diameter hollow pole without webs (Pole-E). The predicted deflection by these models agreed well with those of the experiment, and the predicted normal stress agreed with those calculated. The normal and shear stress distributions inside the members were investigated, and stress distributions in the XY and YZ planes are exhibited. As expected, the webs reduced the local shear stress and improved shear capacity, especially in the top and groundline regions where shear levels were the highest. The webs had little effect on the normal stress. Shear stress increased from the bottom to the top for the members with taper. Large shear stress concentration was predicted in a small region close to the groundlines. The models also predicted that the shear stress of the tapered hollow poles would decrease from the inside to the outside surfaces in XY plane.

References

Adams, R. D., G. P. Krueger, S. Long, A. E. Lund, and D. D. Nicholas 1981. Compole—The composite wood material utility pole. Proc. Am. Wood Protection Assoc. Pp. 1-6.nAmerican Wood Preservers Institute (AWPI). 1996. Wood Preserving Industry Production Statistical Report. 2750 Prosperity Avenue, Suite 550, Fairfax, VA.nBiomimicry. 2006 http://www.biomimicry.net/intro.html'>http://www.biomimicry.net/intro.htmlnBratkovich, S. M. 2002. Markets for recycled treated wood products. Pages 37-40 in Proc. Enhancing the Durability of Lumber and Engineered Wood Products. Forest Prod. Soc. Madison, WI.nErickson, R. W. 1994. The hollowed veneered pole. Pages 465-468 in J. Wells, ed. Proc. Pacific Timber Engineering Conference. Queensland University of Technology, Brisbane, Australia.nErickson, R. W. 1995. Hollow veneered pole. U.S. Patent No. 5,438,812. 1990. Mechanics of materials. 3rd ed. PWSKENT Publishing Company, Boston, MA. 807 pp.nGere, J.M., and S. P. Timoshenko 1990. Mechanics of materials. 3rd ed. PWS-KENT Publ. Co., Boston, MA. 807 pp.nHockaday, E. 1975. What does structural glue laminated wood have to offer the electrical utility industry. in Proc. 6th Wood Pole Institute. Colorado State Univ., Ft. Collins, CO.nMcKain, B. 1975. Laminated wood for utilities—A combination of versatility, economics and beauty. Proc. 6th Wood Pole Institute, Colorado State University, Ft. Collins, CO.nMarzouk, H. M., M. U. Hosein, and V. V. Neis 1978. Built-up utility poles using prairie timber. Forest Prod. J. 28(11):49-54.nPiao, C., T. F. Shupe, and C. Y. Hse 2004. Mechanical properties of small-scale wood-laminated composite poles. Wood Fiber Sci. 36(4):536-546.nPiao, C., T. F. Shupe, R. C. Tang, and C. Y. Hse 2005. Finite element analyses of wood-laminated composite poles. Wood Fiber Sci. 37(3):535-541.nPiao, C., T. F. Shupe, R. C. Tang, and C. Y. Hse 2006. Mechanical properties of small-scale laminated wood composite poles: Effects of taper and webs. Wood Fiber Sci. 38(4): 633-643.nShidles, J. B. Sc. 1970. Adhesive Handbook. CRC Press, A Division of the Chemical Rubber Co., Cleveland, OH.nTang, R. C., and S. F. Adams 1973. Application of reinforced plastics for laminated transmission poles. Forest Prod. J. 23(10):42-46.nUSDA Forest Products Laboratory (USDA FPL). 1999. Wood handbook-Wood as an engineering material. Gen. Tech. Rep. FPL-GTR-113. USDA Forest Service, Forest Prod. Lab., Madison, WI. 463 pp.n

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Published

2008-01-28

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Research Contributions