Stress transformation question
Stress transformation question
(OP)
I have normal stresses in x, y, and z along with shear stress in x-y. I am rotating the coordinates about the z axis, so the normal stress in the z direction should be the same in the new coordinate system as in the old.
My question is, since the stress in z does not change, and since all the other stresses are in the x-y plane, can I use the stress transformation equations attached? They are clearly labeled as being useful for "plane stress and plane strain" situations only(http:/ /en.wikipe dia.org/wi ki/Stress_ %28mechani cs%29#Stre ss_transfo rmation_in _plane_str ess_and_pl ane_strain), but the stress in Z really doesn't seem to have anything to do with the other stresses here.
Any help is appreciated.
My question is, since the stress in z does not change, and since all the other stresses are in the x-y plane, can I use the stress transformation equations attached? They are clearly labeled as being useful for "plane stress and plane strain" situations only(http:/
Any help is appreciated.





RE: Stress transformation question
I leave the maths to you.
Cheers
Greg Locock
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RE: Stress transformation question
your equations are correct for rotating stresses in-plane.
RE: Stress transformation question
Yes you are correct.
These equations are simply Mohr's Circle.
Kenneth J Hueston, PEng
Principal
Sturni-Hueston Engineering Inc
Edmonton, Alberta Canada