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Salutations, 

hi

could any one please tell me how to apply periodic boundary conditions for off axis loading on unidirectional fiber composite.

I am trying to apply the PBC in this paper "Yunfa Zhang ,Zihui Xia,Micromechanical Analysis of Interphase Damage for Fiber Reinforced Composite
Laminates", but the model does not seam right.

Could any one please tell me the steps that I shall take

hi

i wonder how i can apply a shear strain e12 on a node in abaqus!

can it be done by rotation boundary condition?

thanks

hi all

I need help in setting the s23 on a certain surface in my model to be zero. But the following pops up:
"loads must be created with a non zero magnitudes unless utilizing a user subroutine"

what subroutine shall I use and how?

thanks

Hi everyone, 

My name is layth and I am a Msc student doing my master dissertation about advanced composite materials for wind turbine construction. I faced many comlexities with the analytical homogenization because the idea is doing two homogenization steps for composite contains (matrix+glass fibers+nano particles). please, I am asking for anyone coud helps me with how to do the calculation steps to get the effective properties for composites.. I would be so appreciate whatever your do.

kind Regards,

Layth   

I want to know the difference between them and how to determine which one to use

I'm trying to simulate crack growth direction using strain energy density criterion (S)

my specimen is a thick rectangular plate -elliptical surface crack -plane stain

Dear All,

Can anyone tell me that how I can plot the traction-separation for cohesive surface in Abaqus? In XY data, I defined reaction force and displacement and then combine them but the plot was not like the one we have in manual. 

Do I specify RF and U for interaction surface? Do I select just one node or the whole model for RF and U?

Thank you,

Hello everyone, 

Dear All,

I have a UMAT about changing the density of my model,

I do not know how to see the density (or any other arbitrary variables) contours as the result of my process. Should I define any special things?

Any helps would be highly appreciated.

Dear All,

I defined cohesive surface between 2 surface in my model which is 3D but I faced an error which is mentioned below:

In the contact pair, the slave surface contains quadratic triangular facets. This is not allowed for the node-to-surface approach using direct enforcement of the contact constraints. Please  use the surface-to-surface approach and/or penalty enforcement method.