SOL 400: "NSM" IN PSHELL or PCOMP CARDS NOT COMPUTED

[Trezepe]

Hello,
I'm using the MSC SOL 400 for a non-linear transient analysis. I have found out that if I specify a NSM (Non Structural Mass) in the apposite PCOMP/PSHELL field without insert any density value in the material card, during the job-run, the software does not take into account this parameter. So the weight of the structure under study it's not the right weight and all the results are wrong.
Have you ever dealt with a such problem?

Regards

 

[hezhj2000]

It sounds like a bug. You should probably report it to MSC.

 

[Trezepe]

I 'll do it...
Many thanks.

 

[Trezepe]

The problem arises when one uses PCOMP + PSHLN1 cards (Marc advanced nonlinear elements) in SOL 400.....
So in order to obtain the same weight that you have when using the NSM field in the PCOMP card, the first step is to run, for example, a SOL 101 with the following statement (no SPC specified):

SOL 101
.....
ECHO = PUNCH
EXTSEOUT(MASS EXTBULK ASMBULK EXTID=100 DMIGPCH)
SUBCASE 1
....
BEGIN BULK
PCOMP,1,,NSM,......
.....
ENDATA

One of the outputs (in the punch file) will be the MAAX matrix.
Copy it and paste it in an new file. Then, as second step, include it in your SOL 400 master file:

SOL 400
......
CEND
............
ECHO = NONE
$
M2GG=MAAX
$
SUBCASE 1
..........
BEGIN BULK
.........
PCOMP,1,...... $no NSM specified
PSHLN1,1,.......
.........
INCLUDE 'NSM_PCOMP_MASS_matrix.bdf'
........
ENDDATA

That's the way I have obtained the weight I needed.

 

[hezhj2000]

Thanks for the update.