Apadravya wrote:A non circle geometric shape if turned a certain way can fall through, I think.
yup
that's what i was taught in college
round is not prone to falling in the hole.
and its stronger across the middle than a square for example, because the load can be distributed evenly at each edge, where as a square or parallelogram, triangle or some other shape would transmit load to stress points (the corners) and would require a thicker structure
at least that's what i remember but it was long long ago in a land far away
same reason arches are stronger than non arched structures