Is the Maximum Shear Strain Direction Always 45 Degrees?

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temaire
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Homework Statement



14714206e9ccb8064cc7579fbf9cfc640441a831.png


Homework Equations



[tex]\gamma_{max} = {\left|{\epsilon_1} - {\epsilon_2} \right|}[/tex]

The Attempt at a Solution



I calculated the maximum shear strain to be [itex]200 \mu[/itex].

For the angle, I don't know exactly how to go about finding it. However, the solution says that the angle is [itex]45^{\circ}[/itex]. Does this mean that all they were asking was to state the angle between the maximum shear plane and the principal plane, which is always [itex]45^{\circ}[/itex]? Or am I supposed to solve for the maximum shear plane angle by first finding the principal plane angle and subtracting [itex]45^{\circ}[/itex] from it?
 
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You need to get chummy with your buddy the Mohr stress/strain circle... although just looking at the question you could solve it purely from math. I assume you have a solid mechanics or mechanics of materials textbook you could easily find it in there.
 
CJSGrailKnigh said:
You need to get chummy with your buddy the Mohr stress/strain circle... although just looking at the question you could solve it purely from math. I assume you have a solid mechanics or mechanics of materials textbook you could easily find it in there.

Our professor explicitly told us not to use Mohr's circle for this question.

I have tried looking through my mechanics of materials textbook, but couldn't find a way of solving for the direction angle of the maximum shear strain, just with having the principal strains and the maximum shear strain.

I want to know whether the question was supposed to ask you to state the angle between the maximum shear strain and the angle and the principal plane angle. I know this sounds trivial, but the answer to this problem does say [itex]45^{\circ}[/itex].
 
temaire: I currently think you worked the problem correctly. I currently think all they were asking for was to state the angle between the maximum shear plane and principal planes, which is always 45 deg.
 
nvn said:
temaire: I currently think you worked the problem correctly. I currently think all they were asking for was to state the angle between the maximum shear plane and principal planes, which is always 45 deg.

Thank you nvn. That's what I was thinking as well.
 
Always 45 deg. You're right.