Abstract
Combinatorial identities, trigonometric formulas, together with complex variable techniques are used to derive exact and closed expressions for the six flexure functions of certain isotropic cylinders under flexure. The cross sections are bounded either by the closed curvesr=a cosn (θ/n) (−π<θ≦) or the closed curvesr=a∣sin(θ/n)∣n(−π<θ≦), wheren isa positive integer (n>1).
Résumé
Des identiteés combinatoires et des formules trigonométriques avec des techniques de variables complexes sont utilisées pour dériver des expressions exactes et simples pour les six fonctions de flexion de quelques cylindres isotropiques. Les sections sont limitées par les courbes ferméesr=a cosn θ/n(−π≦θ≦π) et les courbesr=a∣sinθ/n∣n(−π≦θ≦π) où est un entier positif (n>1).
Similar content being viewed by others
References
I. Anderson,A first course in combinatorial mathematics, Clarendon Press, Oxford 1974.
L. M. Milne-Thomson,Flexure, Trans. Amer. Math. Soc.90, 143–160 (1959).
W. A. Bassali and S. A. Obaid,On the torsion of elastic bars, Z. Angew. Math. Mech.61, 639–650 (1981).
S. A. Obaid,Flexure of beams with certain curvilinear cross sections, J. App. Math. Phys.34, 439–449 (1983).
J. Riordan,Combinatorial identities, Wiley, New York 1968.
I. S. Sokolnikoff,Mathematical theory of elasticity, 2nd ed., McGraw-Hill, New York 1956.
A. C. Stevenson,Flexure with shear and associated torsion in prisms of uni-axial and asymmetric cross sections, Phil. Trans. Roy. Soc.237, 161–229 (1938).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Rung, D.C., Obaid, S.A. Combinatorics and flexure. Z. angew. Math. Phys. 36, 443–459 (1985). https://doi.org/10.1007/BF00944635
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF00944635