Plate Buckling Clarification

[richardwhitfield]

Hello,

I am quickly trying to see whether buckling of the plate will be a governing case for a simple connection that I am looking at.

I just wanted to check that my approach was correct for this...

I have modelled everything in Shell type structures so that I have all degrees of freedom available.  I have then applied the self weight (almost negligible) and a point ULS live load (hence why the factor in the load combination is only 1).

I have selected non linear buckling analysis in my analysis parameters and run the analysis for 10 mode shapes.

I have then looked at the mode types to see which are applicable to the type of loading that is applied (for the attached model I believe that modes 6, 8 and 9 are applicable and because of other factors for me case 8 is really the critical one).

I have then opened up the critical loads table and checked the coefficient for buckling at the critical case which appears to be approx. 330 for a 16mm thk plate (despite this thickness being called 12thk - i upped this to reduce the plate stresses).  330 Seems like a very high factor for this situation, it means that a load of approx. 1420kN would be required to induce buckling which seems unlikely and hence my trepidation.

I attach my model for you to have a look at.

Any help would be gratefully received.

Regards,

Richard

[Rafal.Gaweda]

Richard,

Maths gives you results as shown below

From engineering point of view you should

look at positive values -> most dangerous are always coeffs <= 1.

In your case the firts positive is 103.

[tony.ridley]

Rafal,

"Maths", or maps??

[Rafal.Gaweda]

English is not my native language 😉 you know but I mean "mathemathical calculations"

http://en.wikipedia.org/wiki/Mathematics

[tony.ridley]

Ah OK.  sorry I wasn't trying to be rude!  

but thanks for the link anyway!