Author Topic: Displacemnt control in the elasto-plastic analysis  (Read 5036 times)

Yijun Chen

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Displacemnt control in the elasto-plastic analysis
« on: August 10, 2020, 07:44:28 AM »
Dear Professors,

I know the command "PROPortional load command" in the feap, and it works well. I want to ask if the feap exists other command "PROPortional displacement command"? I want to use the displacemnt control in the nonlinear analysis. Or is there any method to implement displacemnt control?

Thank you very much in advance!

Best regards,

Yijun Chen

Prof. R.L. Taylor

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Re: Displacemnt control in the elasto-plastic analysis
« Reply #1 on: August 10, 2020, 08:32:27 AM »
You can use proportional loads to control displacements too.  The best commands for veri8.5 and later are

LOAD PROP #you want to use

<DISP,EDIS,CDIS>  Choose and option

LOAD EN

The DIS type commands set a value that the proportional load multiplies, thus you need the PROP too.

Look in user manual for more information.

Yijun Chen

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Re: Displacemnt control in the elasto-plastic analysis
« Reply #2 on: August 10, 2020, 09:13:36 AM »
Dear prof. Taylor,

thank you very much for your Valuable comments.

I am using FEAP 8.3 with user element, and use the "PROPortional load command" .

BATCh
PROP,,j
END
5 0 5E8 0 0 0 0 0

Best wishes,

Yijun Chen

Prof. S. Govindjee

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Re: Displacemnt control in the elasto-plastic analysis
« Reply #3 on: August 10, 2020, 10:34:07 AM »
Best is to upgrade to a newer version FEAP.  8.6 is the current version.

In the older versions you can use FPRO, CPRO, and EPRO to set which dofs are connected to which proportional loads.

Yijun Chen

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Re: Displacemnt control in the elasto-plastic analysis
« Reply #4 on: August 10, 2020, 03:05:41 PM »
Dear prof. Govindjee,

How to upgrade to a new version. How much the ver 8.6?

Best wishes,

Yijun Chen

Prof. S. Govindjee

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Yijun Chen

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Re: Displacemnt control in the elasto-plastic analysis
« Reply #6 on: August 10, 2020, 06:13:55 PM »
Thank you very much.

Prof. R.L. Taylor

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Re: Displacemnt control in the elasto-plastic analysis
« Reply #7 on: August 10, 2020, 06:58:27 PM »
In the meantime, you could try to use

DISP
  list of nodes and dof to apply displacements

FPRO
  list of proportional load numbers for each node and dof you want to activate

Yijun Chen

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Re: Displacemnt control in the elasto-plastic analysis
« Reply #8 on: August 11, 2020, 10:24:45 AM »
Dear prof. Taylor,

thank you very much for your kind help.

Best wishes,

Yijun Chen