Abstract
Funicular structures can resist a given load with pure axial forces and therefore tend to use material very efficiently. One main challenge in their design is form finding, which often requires advanced numerical methods. In this article, we show analytically that a very common family of curves, conics, is funicular for a particular load case: a uniform radial load emanating from a focus. The result is a generalization of the well-known funicularity of parabolas and arcs of circles, respectively, under uniform vertical load and constant normal pressure. It can be used to design self-stressed structures by hand without the need for calculations. Portions of conics can be combined to obtain original shapes.
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This work was supported by Labex MMCD (http://mmcd.univ-parisest.fr/).
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Tellier, X., Douthe, C., Hauswirth, L. et al. Funicularity of conics. Acta Mech 232, 3179–3191 (2021). https://doi.org/10.1007/s00707-021-02987-6
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DOI: https://doi.org/10.1007/s00707-021-02987-6