Stress Concentration Around Knots in Laminated Beams


  • R. C. Tang


Knot effects, orientation of knots, laminated beams, St. Venant's Principle


A formal elastic solution of the stresses and displacements occurring in a laminated beam, with an arbitrarily located elliptic or circular knot, subjected to static bending is presented. The solutions are obtained by using the theory of complex variables in plane elasticity. Numerical examples of the stress concentration are illustrated with graphs in which comparisons are made between the cases of sound knot, decayed knot, knothole, and wooden plug. The effects of size, shape, location, orientation, and material property of the knot on the stress concentrations are discussed.


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Research Contributions