Smart questions
Smart answers
Smart people
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Member Login




Remember Me
Forgot Password?
Join Us!

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips now!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

Join Eng-Tips
*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.
Jobs from Indeed

Link To This Forum!

Partner Button
Add Stickiness To Your Site By Linking To This Professionally Managed Technical Forum.
Just copy and paste the
code below into your site.

kashm (Automotive) (OP)
21 Jun 11 12:09
Does any body know how to convert MAT2 to MAT8 and vice- versa.
Thanks!
rb1957 (Aerospace)
21 Jun 11 12:47
from NASTRAN help ...
MAT2 Shell Element Anisotropic Material Property Definition
Defines the material properties for linear anisotropic materials for two-dimensional elements.

defines Gij such that stress_i = Gij*strain_j (i think !?)
field3 = G11,
field4 = G12,
field5 = G13,
field6 = G22,
field7 = G23,
field8 = G33

and MAT8 Shell Element Orthotropic Material Property Definition
Defines the material property for an orthotropic material for isoparametric shell elements

field3 = E11 = G11 (ie field3 from MAT2)
field4 = E22 = G22 (ie field6 from MAT2)
field5 = nu12 = G12/G11 (MAT2 field4/field3)
field6 = G12 = G33 (ie field8 from MAT2)
field7 = G13 = field5 on MAT2
field8 = G23 = field7 on MAT2

i tried to copy the manual, but the tables wouldn't show properly.

GL
SWComposites (Aerospace)
22 Jun 11 12:39
at one time you could input a PCOMP/MAT8 set and NASTRAN would calculate the effective PSHELL/MAT2 card set.

In general there is no unique solution for going from homogeneous PSHALL/MAT2 stiffness to layered PCOMP/MAT8 stiffness.
rb1957 (Aerospace)
22 Jun 11 12:50
"In general there is no unique solution for going from homogeneous PSHALL/MAT2 stiffness to layered PCOMP/MAT8 stiffness."

if that means determining individual ply properties from the composite, then yes (FWIW) i agree.

but if you're going from bulk section property to bulk section property ... ie you've got a CQUAD with a MAT2 material definition, and you want to use (for whatever reason) a MAT8 card, then (again, FWIW) i'd disagree ... i think i've shown that the MAT8 fields can be calculated from the MAT2 data (and vis versa)
kashm (Automotive) (OP)
28 Nov 11 11:32
I'm sorry for my delayed response. The inputs are very helpful.
@rb1957 ur tipp for converting MAT2/Shell to MAT8/Shell worked.

Thanks a lot!!

Cheers!

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close