Manually record fiber element

[yuweihwang]

Hello folks,

Will the recorder commend change if I used STKO to build the fiber element?
I mannualy add "eval "recorder Element -file Fuse.out -time -dT -ele 17 section 5 fiber 0.0 -0.15 stressStrain" in the script to
record the stress-strain response of the fuse. I also checked the location (y,z) on the section. However, the result is always blank.
Is there any other way to record the stress-strain response of the fiber?

Best,
Yu-Wei Hwang

[STKO Team]

STKO does not change the commands you can use in OpenSees.
By the way, STKO uses a 0-based indexing for gauss points and fibers, while OpenSees uses a 1-based indexing for gauss points and 0-based for fibers.

So in your case it should be:
recorder Element -file Fuse.out -time -dT -ele 17 section 6 fiber 0.0 -0.15 stressStrain
or
recorder Element -file Fuse.out -time -dT -ele 17 section 6 fiber 3 stressStrain

if the first does not work it means that the location is not correct

[netoprax]

I have the same issue
I am sure I am providing the right element, section and fiber number (and coordinates)
unless I misunderstood something
is there anyone willing to help?
thanks

[netoprax]

if anyone come across this post in the future:
removing "-time" worked for me to retrieve to stressStrain.

[Lei Lei]

Dear STKOteam,

I also met this problem and I didn't use MPCOrecorder.

I used a custom script to record the fiber stress-strain results for a zero-length section element like "recorder Element -file Stress-Strain.txt –time -ele 35 section 26 fiber 13.5 0.0 11 stressStrain".

However, it didn't work and the Stress-Strain.txt was blank.

I also tried with ""recorder Element -file Stress-Strain.txt –time -ele 35 section fiber 13.5 0.0 11 stressStrain"
and "recorder Element -file Stress-Strain.txt –time -ele 35 section fiber 13.5 0.0 stressStrain"
and "recorder Element -file Stress-Strain.txt -ele 35 section 26 fiber 13.5 0.0 11 stressStrain".

All the efforts were in vain.

Looking forward to your reply.

[kesavapraba]

Hi, Can you please share a minimal example model for debugging?

[Lei Lei]

Thanks for your reply!

I have done it with the help from https://opensees.berkeley.edu/OpenSees/ ... al/259.htm

And for the zerolengthsection element, the number of section should be removed, just like 'recorder Element -file ele1sec1StressStrain.out -time -ele 1 section fiber $y $z <$matID> stressStrain'.

[kesavapraba]

There is a long dash before "time", you should use small dash instead, this can be a reason for the first two cases. However, your last case should have worked without "-time" option, Not sure why in that case! Can you try following:
recorder Element -file StressStrainCurve.out -time -ele 35 section 26 fiber 13.5 0.0 11 stressStrain