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arXiv · 1505.02255

A hypergeometric treatment to explain the nonlinear true behavior of redundant constraints on a straight elastic rod

Giovanni Mingari Scarpello·Daniele Ritelli
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Abstract

In theory and practice of elastic straight rods, the statically indeterminate reactions acted by perfect constraints are commonly believed not to depend on the flexural stiffness $EJ$. We solve exactly two elastica problems in order to obtain hypergeometrically (helped by Lagrange, Lauricella, Appell), the true displacements upon which the forces method is founded. As a consequence, the above reactions are found to depend on stiffness: the presumptive independence credited as general, is far from being always true, but, quite the contrary, is valid only within a first-order approximation.

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Giovanni Mingari Scarpello, Daniele Ritelli. 2015-05-09. A hypergeometric treatment to explain the nonlinear true behavior of redundant constraints on a straight elastic rod. https://arxiv.org/abs/1505.02255

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