Abstract
The history of structural optimization as an exact science begins possibly with the celebrated Lagrange problem: to find a curve which by its revolution about an axis in its plane determines the rod of greatest efficiency (Lagrange 1868). The Lagrange hypothesis, that the optimal rod possesses the constant cross-section was abandoned for Euler buckling problem (Tadjbakhsh and Keller, J Appl Mech 29:159–164, 1962). In this Article the Lagrange hypothesis is proved to be valid for Greenhill’s problem of torque buckling. The corresponding isoperimetric inequality is affirmed.
References
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Kobelev, V. Confirmation of Lagrange hypothesis for twisted elastic rod. Struct Multidisc Optim 46, 155–157 (2012). https://doi.org/10.1007/s00158-012-0773-9
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DOI: https://doi.org/10.1007/s00158-012-0773-9