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Re: Furculae, Form and Function




Jaime A. Headden wrote:

>  Such a shape, like an I-beam, is
> very stably an anti-compression element.

I-beams are usually selected to resist bending in the plane of the shear
web.  Straight compressive loads are often a secondary consideration for
I-beams.  Some other shapes can be more efficient in compressive column
loading because they have greater column stiffness for a given amount of
material.  Circular tubes for example.

> However, the rounder the shaft, the easier to bend.

For a closed boundary with a constant circumference, increasing the
ellipticity will make the shaft more difficult to bend in the plane
perpendicular to the short axis of the ellipse and easier to bend in the
plane perpendicular to the long axis. The rounder the shaft, the greater
the torsional stiffness.  In general, the rounder the shaft, the more
difficult to bend.

All the best,

Jim