Shear Stress in a tensile test
Shear Stress in a tensile test
(OP)
Hi,
I was under the impression that in a simple tensile test there is no shear present but have now been told by my mentor that even in a simple tensile test shear is present. To understand this I was told to think of Mohr's circles and rotate the coordinate system by 45 degrees. I am struggling to understand this and have looked for references but fail to find any. I would appreciate any guidance ASAP.
Thanks,
Hooman
I was under the impression that in a simple tensile test there is no shear present but have now been told by my mentor that even in a simple tensile test shear is present. To understand this I was told to think of Mohr's circles and rotate the coordinate system by 45 degrees. I am struggling to understand this and have looked for references but fail to find any. I would appreciate any guidance ASAP.
Thanks,
Hooman






RE: Shear Stress in a tensile test
1) draw a square representing your infinitesimal stress element.
2) add arrows to the sides of the square representing shear stresses for the pure shear case. Make sure that the arrows are drawn such that the element is in equilibrium. You should have two corners with just arrow heads and two with arrow tails.
3) cut your square along a diagonal connecting the arrow tails and isolate one of the resulting half square triangles as a free body diagram.
4) sketch the resulting force required on the diagonal to keep the new free body diagram in equilibrium. It should be a pure tension force oriented normal to the diagonal.
The above procedure shows that, where there is pure shear, there is tension. If you accept that the reverse is also true, then you should be convinced that, where there is pure tension, there is shear..
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: Shear Stress in a tensile test
RE: Shear Stress in a tensile test
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RE: Shear Stress in a tensile test
For me, the part was loaded in tension. Part of the "similtude" between the test piece and the work piece is how well does the work piece mimic the test piece ?
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RE: Shear Stress in a tensile test
RE: Shear Stress in a tensile test
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