So far we’ve only looked at 2D plane-stress scenarios, but in the real world stresses act in a *3D manner*, with a general state-of-stress that looks like:

The full-blown transformation for this scenario is not within the scope of this course (phew…). But we will be looking at a simple 3D scenario: zero-stress in the 3rd direction:

So far we’ve only looked at 2D plane-stress scenarios, but in the real world stresses act in a *3D manner*, with a general state-of-stress that looks like:

The full-blown transformation for this scenario is not within the scope of this course (phew…). But we will be looking at a simple 3D scenario: zero-stress in the 3rd direction:

In this case, all we have to do is to add a 3rd point of Z(0,0) in our existing 2D Mohr’s circle.
We then draw our *3D Mohr’s circle* which allows us to calculate our absolute maximum shear stress τ_{abs-max}.

Here’s some possible configurations of our 3D Mohr’s circle:

Doesn’t seem too difficult to draw does it? Let’s look at an example now.

In this case, all we have to do is to add a 3rd point of Z(0,0) in our existing 2D Mohr’s circle.
We then draw our *3D Mohr’s circle* which allows us to calculate our absolute maximum shear stress τ_{abs-max}.

Here’s some possible configurations of our 3D Mohr’s circle:

Doesn’t seem too difficult to draw does it? Let’s look at an example now.