Specifying 2 input forces in NonLinear Analysis in FEMAP v9.31

[mghanem]

Hello,

I have a nonlinear shear buckling problem to run and I have a question about how to do it in Femap. When I used Ansys I can specify 2 input file, where in the first file I apply a small linearly increasing out-of-plane force (to initiate imperfection). Then the second input is a a linearly increasing force (in the shear direction). Then I look at force vs. displacement curve to determine point of instability and failure.

Now in Femap, I am trying to to do the same thing, however, I do not know/not sure how. How can I apply multiple varying forces vs. time curves such that it will run the first one, then stop running it and read the second one and run it (it seems all I can do is run both at the same time)

Thanks.

 

[BlasMolero]

Hello!,
I understand you run FEMAP with NX NASTRAN. You have two options:
• Use NX NASTRAN RESTART capability, or
• Create TWO Load Sets in order to simulate the first one loading he imperfection condition and the second one the service loading.

Assuming you select the second method when using more than one LOAD CASE then the IMPORTAN KEY is use MULTIPLE CASES for Nonlinear Static Analysis using the FEMAP Analysis Set Manager:
• In the Boundary Conditions dialog box:
- Select “0..None” from the Constraints drop-down list
- Select “0..None” from the Loads drop-down list

• In the Analysis Set Manager dialog box:
- Click Multi-Set button
- Click "Select All" for both COSNTRAINT SETS and LOADING SETS

• In the Analysis Set Manager dialog box you will see that "Two cases have been created".
- Click "Analyze" to wun the nonlinar analysis.

Best regards,
Blas.

~~~~~~~~~~~~~~~~~~~~~~
Blas Molero Hidalgo
Ingeniero Industrial
Director

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