Learning Forum

[Sokpanha Mao]

Dear everyone,

Currently, I am working on model validation by comparing the results of the strain in the rebar at a node or some locations from the experiment with the simulation.
Could anyone guide me on how to get this result in LS-DYNA Workbench or LS-Prepost?

Thank you

[Tonmoy]

 

Hello Sokpanha,

Those rebars looks great! How did you generated those? I mean which elements did you utilize and how did you modeled them? Did you import them as IGES or STP or did you do the modeling directly using workbench?

 

Thanks,

Tonmoy.

 

[Sokpanha Mao]

Hello Tonmoy,

I have been modeling and analyzing in LS-DYNA workbench. I imported d3plot file and am trying to view some results in LS-Prepost.

Best regards,
Panha

[YINGHAO TIAN]

If you modeled these with beam elements, you can plot the stress/strain using LSPP fringe plots.

[Sokpanha Mao]

Thanks YINGHAO TIAN,

I modeled reinforcement elements as beam elements. In LSPP fringe plots, I tried to check and I could only get the strain of reinforcement for the whole structure like this.

However, I want to compare the strain of rebars at a point from the experiment with the simulation result. Could we do that? As I modeled the reinforcements as beam elements and if we could not do that in LSPP, what are the reasons for that?
I really appreciate your response.

Best regards,
Panha

[YINGHAO TIAN]

I am not sure what your question is. From LSPP fringe plot, you get the strain at the location you want. And you have experiemntal data to compare. 

[Sokpanha Mao]

 

Thank you Yinghao Tian,

I might get it wrong on how to view strain results as I could not find the way to do it. Could you elaborate more on the steps to get the strain of rebar at the location through the Fringe plot, please?
This is the view from LSPP.

Best regards,
Panha

 

[YINGHAO TIAN]

I am not 100% sure for the beams, but I think you can go to "EleTol", then "Identify", select "Element" (Integration point) and check "Show Results", and select the element(s) at your desired location.

[Sokpanha Mao]

Thanks Yinghao Tian,

I tried to follow your suggestion. When I select the element, how can I identify the integration point? because I would like to select a node on the rebar to view the result on that node.


Best regards,
Panha

[YINGHAO TIAN]

Stress/strain is element value. The integration points are listed in the window below in the UI.

[YINGHAO TIAN]

see,

/knowledge/forums/topic/how-to-output-the-stress-and-strain-at-the-integration-points-of-integrated-beam-elements/

https://www.dynasupport.com/howtos/element/beam

[Sokpanha Mao]

Thanks Yinghao Tian,

I have been reading them. I have a question on how to input the value of "BEAMIP".



Best regards,
Panha

[YINGHAO TIAN]

That is related how the beams were defined in the model.

[Sokpanha Mao]

Dear Yinghao Tian,

Could you elaborate more or give an example of this? When we put BEAMIP=1 or 2, how is the integration point?
Thank you

Best regards,
Panha

[YINGHAO TIAN]

How were the beams defined? If you defined beams with 4 integration points, I would put the same number here.

[Sokpanha Mao]

Thank you very much for your advice and recommendations. I could select the nodes and elements to find the strain results in the rebars now.