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Import from Nastran (BDF): Missing Material Properties

Import from Nastran (BDF): Missing Material Properties

Import from Nastran (BDF): Missing Material Properties

(OP)
Hi All,
I am looking at a very large Nastran model in .bdf format. I have imported into Abaqus and tried to run a frequency analysis. The error message is returned that material properties are missing from about ~1% of the elements (7000 in total).
I have looked at the ErrElemMissingSection in the ODB and they seem to be distributed throughout the model. I am assuming that this is an error when importing the BDF, and I will have to go in and manually assign sections / material properties to these elements. Is there any easy way of doing this?
Is it possible to export the element set ErrElemMissingSection from the ODB and import it into the CAE file so I can then assign material properties to that set??
Any advice would be much appreciated.

Regards,

Nigel
 

RE: Import from Nastran (BDF): Missing Material Properties

Create Display Group<Element Sets, select the ErrElemMissingSection group, and hit the "Replace" Boolean. This should remove all the properly assigned elements from the display.
Tools<Query, "Active Elements". This will spew out the list of elements labels that are displayed in the message box. You can copy/paste this into an input file, Excel, what have you.
Just a warning of experience though; if you copy and paste these into an input file, Abaqus can only read in 16 entries per line and will forget the rest in that line, so if you have more than 16 in a line, you have to line break it down to size. Hope it helps!

RE: Import from Nastran (BDF): Missing Material Properties

(OP)
Thanks for that Nileo,
I have pasted the missing elements into the INP file and done...
*Element, type=??
<paste element numbers here>
and
*Elset, elset=NAME_of_Elementset, instance=PART-1-1
<paste element numbers here>

I am not sure what elemnet type to use for these very thin 'line' like elements. Does any one have any suggestions?

Once I have an element set I should be able to assign material properties, or just delete the elements with missing properties.

I have tried to attached a photo of the elements.

Regards,

Nigel

 

RE: Import from Nastran (BDF): Missing Material Properties

You shouldn't have to put those labels in the *Element section. They already have an element label, which is what that "Active Elements" output. Those particular elements are just missing from the *Elset that is later assigned the section type, like shell or membrane section, and unless those elements are different from their adjacent elements, you can just throw it in the group with them. Query a touching element for its Section:ElementSet and throw in your rogue elements in that set. If its still giving you a hard time and its not confidential or anything, throw up the input on here and I'll take a gander.

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