Composites Failure Question
Composites Failure Question
(OP)
Hello,
I have a question about interlaminar shear failure of composites, specifically pertaining to finding an appropriate interlaminar shear stress using Nastran.
I'm analyzing a carbon fiber overwrapped pressure vessel (COPV). In the region I'm looking at I have modeled two plies; one 17 deg ply and one -17 deg ply.
The nastran output gives stresses/strains in the fiber and matrix directions however gives interlaminar shear in the defined elemental material direction (0 deg in this case).
My question then is would it be appropriate to RSS the shear stress in the XZ and YZ directions to establish a maximum interlaminar shear stress? Is there some transformation that should be applied to yield the max interlaminar shear stress?
Any advice would be greatly appreciated...
Thanks much
I have a question about interlaminar shear failure of composites, specifically pertaining to finding an appropriate interlaminar shear stress using Nastran.
I'm analyzing a carbon fiber overwrapped pressure vessel (COPV). In the region I'm looking at I have modeled two plies; one 17 deg ply and one -17 deg ply.
The nastran output gives stresses/strains in the fiber and matrix directions however gives interlaminar shear in the defined elemental material direction (0 deg in this case).
My question then is would it be appropriate to RSS the shear stress in the XZ and YZ directions to establish a maximum interlaminar shear stress? Is there some transformation that should be applied to yield the max interlaminar shear stress?
Any advice would be greatly appreciated...
Thanks much





RE: Composites Failure Question
RE: Composites Failure Question
Nastran allows use of an allowable interlaminar shear stress. It might pay to check out how this is handled. Does Nastran do an RSS to compare with the allowable?
A pressure vessel shouldn't have that much ILSS knocking about. Are the values significant?