Question

Maybe misunderstanding stress elements?

Answer 1

So I'm looking at a problem

Answer 2

Where the idea is to find the factor of safety at elements A and B

But don't worry about that, I'm just setting up the stress elements for now

Answer 3

So if I'm looking at element A

We have an axial force, NO bending force, and a torsional force

If we look at B...we have the same axial force, NOW a bending force, and also a torsional force

Answer 4

So when I set up my 2-D elements..wouldn't they look like:



From that...we would have equations for A like:

\[\large \sigma _x = \frac{P}{A}\]
\[\large \tau_{xy} = \frac{Tr}{J} + \frac{VQ}{It} \]

and for B:

\[\large \sigma _x = \frac{P}{A}\]
\[\large \sigma _y = \frac{Mc}{I}\]
\[\large \tau _{xy} = \frac{Tr}{J}\]