Buckling Calculation

[deployedsearch]

Hello All,
Are there are any equations which take into account combined loading (bi-axial compression,shear and in plane bending) into account in calculating a buckling allowable for composite (or isotropic) flat plates with four edges SS. Thanks.

 

[RPstress]

Not aware of anything with precisely that combination. ESDU 81047 does biaxial plus shear for symmetric (specially orthotropic) laminates. You'll probably find that it's conservative if the in-plane bending load is taken as simple compression with the max compressive load per inch. It also lets you allow for through thickness flexibility.

NASA TP 3659, "Buckling Behavior of Long Symmetrically Laminated Plates Subjected to Shear and Linearly Varying Axial Edge Loads," has some good background and handles anisotropy but doesn't itself give you exactly what you want.

http://ntrs.nasa.gov/search.jsp?N=0&Ntk=all&Ntx=mode matchall&Ntt=TP+3659

should find it. The author, Nemeth, has written a few reports on these matters.

Please let us know if you find anything better.

Not sure what the primes may have by way of interaction curves for this stuff. I'll have a check.

 

[SWComposites]

See this paper:

http://www.swcomposites.com/Papers/Buckling_Laminated_Shells_AIAA_1987.pdf

the method includes in-plane axial and shear loads; does not include in-plane bending. If in-plane bending loading conditions need to be considered, then a FE model approach is probably needed.