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arXiv · 2510.19284

On the governing equations of membrane O surfaces

Yoshiki Jikumaru
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Abstract

It is known that a shell membrane in equilibrium where a constant purely normal load $q_n$ acts on the membrane, and where the principal curvature lines coincide with the principal stress lines, forms an integrable system called a membrane O surface. This paper formulates the governing equations for membrane O surfaces of the 1st and 2nd kind, which are analogues to Guichard surfaces of the 1st and 2nd kind introduced by Calapso. Furthermore, under this formulation, we show that membrane O surfaces are a subclass of Demoulin's $Ω$ surfaces, and that the Bäcklund transformation for membrane O surfaces preserves membrane O surfaces of the 1st and 2nd kind, respectively.

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Yoshiki Jikumaru. 2025-10-22. On the governing equations of membrane O surfaces. https://arxiv.org/abs/2510.19284

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