steel coulmns loading

[elogicca]

Is there a table or calculations for figuring out how much weight a column can tolerate?

Lets say 4' piece of 2" square tube 1/8" wall thickness, how much weight can be applied before it starts to deflect?

[dberndt]

.0000000000000000000000001lb.

Any load will deflect the beam, its just a matter of how much.

[fyffe555]

Look up Euler's Formula. Basically the critical buckling load (beyond elastic limit) for a vertical column is;

Fcr=(ExIxPi^2)/L^2

Where;
Fcr=critical force or load,
E=youngs modulus for material,
I = area moment of inertia of the horizontal cross section
L= column length

note that critical load decreases with the square of the column length

L used in the formula changes depending on how the ends of the column are terminated. There's a table somewhere but if the ends are clamped solid then L = 0.5 x actual length. If they're free to float it's 2.0 x actual length and various permutations in between.