Column buckling for tapered/variable cross-section beams

[netvertise]

I have a tapered column, distributed axis load, one end fixed, one end pinned. I would appreciate if anyone can recommend an analysis method or reference to account for fixed-pinned end fixity since standard fixity coefficients do not apply to columns with variable cross sections.

I've looked at Bruhn and Niu and don't feel that they provide adequate analysis direction or address them in sufficient detail.

 

[GregLocock]

If you go back to the basic theory for Euler buckling you should be able to come up with a numerical equivalent to his algebra, able to incorporate variable I and so on.

Remember, all he did was identify an alternative shape for the column that could support the load in bending instead of in compression.

There is probably a neat energy based method.

Cheers

Greg Locock

SIGlease see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[rb1957]

it's not (IMHO) very straight-forward to solve.

McCoombs supplement to Bruhn has a calc for stepped columns that could be applied, and could be modified for the varying axial load.

personally i'd make a simple 1D beam model in FE and obtain the eigenvalue whihc is the critical load in compression.