Composite Interlaminar shear stress

Altair Forum User
Altair Forum User
Altair Employee
edited October 2020 in Community Q&A

Hi everyone,

 

I have a question about how the interlaminar stresses are calculated in shell element. I cant find it in the software documentation I have.

The thin shell element model does not calculate the interlaminar stresses or shear stresses right?

So there is a need to calculate it in another way, does it uses the equilibrium:

 

xTension/dx + xyShear/dy + xzInterLamShear/dz = 0?

 

What about in the free edge, does it assume zero there?

 

What's the failure criteria used? Is it a quadratic considering both xz and yz InterLamShear or just linear?

 

Sorry for so many questions but I need to justify this in my master thesis.

 

Thank you very much,

Best regards

Gonçalo

Answers

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited December 2016

    Hi GonPer,

     

    The composite interlaminar stresses are calculated based on the first-order shear deformation laminated plate theory.

     

    You can refer to any Mechanics of Composite book for more information on the same.

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited December 2016

    Hi Prakash,

     

    Thank you very much for your answer.

    I can justify it that way.

     

    What about de failure criteria? Is it linear or quadratic?

     

    Best regards,

    Gonçalo

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited December 2016

    Hi everyone,

     

    For those who might need to know this, I've calculated it by hand and it looks like this:

     

    BondCrit = ((tau_xz/ILSS)^2+(tau_yz/ILSS)^2)^0,5

     

    Best regards,

    Gonçalo