Thin-shell structure

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Shell structure of the TWA Flight Center Building by Eero Saarinen, John F. Kennedy International Airport, New York

Lattice Shell of the Shukhov Hyperboloid Tower. Currently under threat of demolition.

Great Court, with a lattice thin-shell roof by Buro Happold with Norman Foster, British Museum, London

Thin-shell structures are light weight constructions using shell elements. These elements are typically curved and are assembled to large structures. Typical applications are fuselages of aeroplanes, boat hulls and roof structures in building.

A thin shell is defined as a shell with a thickness which is relatively small compared to its other dimensions and in which deformations are not large compared to thickness. A primary difference between a shell structure and a plate structure is that, in the unstressed state, the shell structure has curvature as opposed to plates structures which are flat. Membrane action in a shell is primarily caused by in-plane forces, though there may be secondary forces resulting from flexural deformations. Where a flat plate acts similar to a beam with bending and shear stresses, shells are analogous to a cable which resists loads through tensile stresses. Though the ideal thin shell must be capable of developing both tension and compression. ^[1]