APDL: SHELL181 stress decomposition- SMISC 34 to 47

[SuG89]

Hello everyone,

For SHELL181 element, SMISC quantities from number 34 to 47 are;

Sm: 11, 22, 12 Membrane stresses

Sb: 11, 22, 12 Bending stresses

Sp: 11, 22, 12 Peak stresses

St: 13, 23 Averaged transverse shear stresses

There is an option of stress linearization in Path operations which returns membrane, membrane+bending and total stresses. Are the above listed SMISC quantities doing the same thing as the stress linearization option under 'Path operations'?

Where can I find more information on how these quantities are being calculated by Ansys? I searched the manual but could not find information about the background theory for these SMISC quantities.

The purpose of my analysis is to study whether the dome structure is in a very good membrane state (negligible bending) or significant bending state. I think this can be done using Sm and Sb.
_________________
Best regards,
Sushant Goel
MSc Uni Stuttgart

 

[rickfischer51]

Make a simple model and compare it to hand calculations.

Rick Fischer
Principal Engineer
Argonne National Laboratory

 

[SuG89]

Ok Mr Fischer. Thank you.

Best regards,
Sushant Goel
MSc Uni Stuttgart

 

[rickfischer51]

Yeah, but did you do it? Or did you pester the folks over at xansys?


Rick Fischer
Principal Engineer
Argonne National Laboratory

 

[SuG89]

Dear Mr Fischer,

I found the relevant formulas in section '2.3.3. Shell Element Output'. Also, I made a small plate model in APDL with the longitudinal direction of plate aligned to x-axes. From contour plot> element solution> stress > sx, I got the top (-0.292) and bottom (0.142) surfaces total stress.

Then, I used the element table options to get N11 stress (-0.074) and SB11 stress (-0.217).

-0.074 + (-0.217) = -0.291
-0.074 - (-0.217) = +0.143

Best,
Sushant Goel
MSc Uni Stuttgart