In article , IMM wrote:


"Mike Clarke" wrote in message
...

[Snip]

But the original question was "Is there any preference between straight
cut ( |_| ) or 'U' shape notches ?". The U shape will be stronger so
would be preferable even if the regs don't require it.

The beam is not weaken any less by having a U shape.

The stress concentration factor for a sharp corner is _much_ greater
than a corner with a generous circular profile. How do you account for
the stress difference not affecting the strength?

--
Mike Clarke