Thank you for your answer Mapes. A follow up question: I have seen von Mises stress represented several ways,
1) vonMises = sqrt (((S1 - S2)^2 + (S2 - S3)^2 + (S1-S3)^2)/2)
where S# represents principal stresses (found from mohr's circle or transformation equations)
2)...
So I understand how to use Mohrs circle and the transformation equations to find principal stresses and stresses for a given plane, but what is the point? Is there a purpose to knowing this other than finding stresses for a given direction, the stress invariants or that shear does not occur on...