Recording Stresses and Strains in 4 Noded Quad Elements

laskar · Post by **laskar** » Thu May 08, 2008 11:13 am

I am using the 4 Noded Quad elements in my analysis.
I need to record the stresses and strains at the 4 nodes of the element in an output file. Is it possible to do so using the recorder command in Opensess.

If yes, can somebody give the tcl/tk command statement for the above.

silvia · Post by **silvia** » Thu May 08, 2008 12:26 pm

you might want to research the forum.

laskar · Post by **laskar** » Thu May 08, 2008 1:05 pm

Has this question been answered in this forum before?

silvia · Post by **silvia** » Thu May 08, 2008 1:06 pm

i believe so, yes.
i am no expert on those objects, so i don't have an answer.

laskar · Post by **laskar** » Thu May 08, 2008 1:38 pm

I browsed through the forum and could not find any topic giving the exact answer to my question. Could you please let me know if you know someone who is an expert in this topic and can help me out?

enginbal · Post by **enginbal** » Tue May 20, 2008 5:18 am

This is a big issue in OpenSees. As far as I know, you can not do it for the time being. I had the same problem with Brick8N elements. Please see; opensees.berkeley.edu/community/viewtopic.php?t=4604&highlight=brick8n&sid=525feedf1c89c848f8e33f7bc22033a5

I would imagine that the most important output of quad-shell-brick elements would be stresses and strains; however, it is impossible to take these outputs in OpenSees.

Good luck ...

bayram_aygun · Post by **bayram_aygun** » Fri May 30, 2008 7:14 am

Hi,

It's really disappointing. I tried to measure the pore pressure in a quad element, for this purpose I needed the stresses on it before and after the earthquake. I couldn't do it.

One of the main purposes of using quad elements is to be able to see how the pore pressure evolves in time. My model (PDMY, FSP, Quad, PyLiq1) only works in v1.7.5Beta and in that version I couldn't get the stresses in quad elements.

Does anyone know how to solve this problem?

Thanks a lot,