Unable to find Gauss point of structural element in post processing

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2443631711@qq.com
Posts: 31
Joined: Tue Nov 22, 2022 10:24 am

Unable to find Gauss point of structural element in post processing

Post by 2443631711@qq.com » Sun Mar 19, 2023 3:37 pm

Dear stko team
I have established a model of an underground structure using Rectangular FiberSection and forcebeam column element, while soil is simulated using quadup element. The model can run successfully, but in the post processing Gaussian point plot, there is no Gaussian point in the structure, and I cannot obtain the stress and strain of the structure. Is there a problem with where my model was set? I will attach my model below
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zou.rar
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2443631711@qq.com
Posts: 31
Joined: Tue Nov 22, 2022 10:24 am

Re: Unable to find Gauss point of structural element in post processing

Post by 2443631711@qq.com » Sun Mar 19, 2023 3:40 pm

like this
The presence of Gaussian dots can be clearly seen in the soil element, but not in the structure
Attachments
屏幕截图 2023-03-19 233956.png
屏幕截图 2023-03-19 233956.png (68.05 KiB) Viewed 531 times

STKO Team
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Joined: Tue Oct 29, 2019 8:45 am

Re: Unable to find Gauss point of structural element in post processing

Post by STKO Team » Mon Mar 20, 2023 9:05 am

It's because you are using the ElasticBeamColumn element. Since it is an elastic element it's analytically integrated (does not have gauss points or fibers in gauss points).
You can ask for "localForce" results and you will be able to see a beam diagram plot.

Otherwise use a generic ForceBeamColumn, and build a Fiber section with uniaxial materials, and you will be able to check:
  • section.force (or section.deformation) in the gauss plot (beam integrated forces/deformations)
  • section.fiber.stress (or section.fiber.strain) in the fiber plot

2443631711@qq.com
Posts: 31
Joined: Tue Nov 22, 2022 10:24 am

Re: Unable to find Gauss point of structural element in post processing

Post by 2443631711@qq.com » Mon Mar 20, 2023 10:21 am

Dear stko team
I modified my model, used the forcebeamcolumn element, and established a fiber section. However, I still cannot see the Gaussian points of the structure during post processing. I attached my model below, and I don't know what went wrong
Attachments
zou.zip
(285.73 KiB) Downloaded 5 times

STKO Team
Posts: 1811
Joined: Tue Oct 29, 2019 8:45 am

Re: Unable to find Gauss point of structural element in post processing

Post by STKO Team » Tue Mar 21, 2023 8:50 am

For a Gauss Plot you can see section.RESULT (i.e. a RESULT located at the section-gauss-point):
BEAM_GAUSS.png
BEAM_GAUSS.png (78.15 KiB) Viewed 484 times

For a Fiber Plot you can see a result like section.fiber.RESULT (i.e. a RESULT located at every fiber of section-gauss-points):
BEAM_FIBER.png
BEAM_FIBER.png (120.21 KiB) Viewed 484 times
Note: Due to a recent change in OpenSees, if you use a Section Aggregator with a Fiber Section inside, you need to specify twice the "section" keyword, like section.section.fiber.RESULT
BEAM_FIBER_CUSTOM.png
BEAM_FIBER_CUSTOM.png (95.77 KiB) Viewed 484 times

Here's a modified file:
zou.zip
(268.23 KiB) Downloaded 6 times

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