×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

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

*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.

laminate composite, bricks & MAT9

laminate composite, bricks & MAT9

(OP)
Hi there!
I'm trying to model a laminate composite by means of 1 layer of bricks and using a MAT9 card for this. The question is: Gij terms point to Ex,Ey,Ez,Gxy,Gyz,Gxz and the poisson's ratios of the entire laminate. I think Ex, Ey, Gxy and Nuxy can be obtained using the classical laminate theory for 2D, but how about the other terms?
I think Ez can be estimated considering the laminate like serial springs. Does anyone know where can I find something about this?
The laminate is made of 12 layers, fabric and tape and the known constants are E1,E2,N12 and G12.
Thanks!

RE: laminate composite, bricks & MAT9

If you are using MSC they should have a MATORT dedicated to 3d orthotropic materials.  For NEi Nastran use MAT12.  See MSC Linear manual materials chapter for info on MAT9 setup for orthotropic materials.

RE: laminate composite, bricks & MAT9

(OP)
many thanks fkmeyers for your answer, the model will run on Nastran 2001 and the solution is gonna be 101. The MATORT is only for sol 600. The linear statics book gives the expresions for Gij in terms of the elastic constants for the entire laminate, the problem remains, is there a way to estimate this elastic constants? Does anyone know about a laminate theory which gives us a out-of-the-plane elastic constants?
thanks!

RE: laminate composite, bricks & MAT9

Cdz -

also, using one liniar solid element thru the lamiante thickness is a very bad idea if you have any bending loads/deformation on your structure.  In general, solid elements are very poor in bending.  What are you trying to model and what results are you trying to obtain?

Steve

RE: laminate composite, bricks & MAT9

(OP)
Hi
Im trying to modelate a single lap shear composite adhesive union, for several reasons the composite is gonna be modeled with bricks and also the adhesive. The material is AS4/8552 fabric and tape and the stacking sequence is:
Fabric(+-45)
Fabric(+-45)
Tape (0)
Tape (0)
Fabric (0/90)
Fabric(+-45)
Symetric
Can I use the recomendations given in those post?

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Resources

White Paper - A Guide to 3D Printing Materials
When it comes to using an FDM 3D printer effectively and efficiently, choosing the right material at the right time is essential. This 3D Printing Materials Guide will help give you and your team a basic understanding of some FDM 3D printing polymers and composites, their strengths and weaknesses, and when to use them. Download Now

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:

• Talk To Other Members
• Notification Of Responses To Questions
• Favorite Forums One Click Access
• Keyword Search Of All Posts, And More...

Register now while it's still free!