Structural column strength chart 1

[amorrison]

Is this chart available anywhere for different wall thicknesses and sections.

http://www.rotaryeng.net/bucktube.gif

If it available in a book I will buy the book.

 

[Kwan]

That chart looks like Johnson buckling curves. These Johnson buckling charts are based on crippling strength and column length. Where did your chart come from?

 

[rb1957]

johnson introduced a parabolic cut-off to the euler column curve ... these curves look a little more simplistic.

bruhn (probably niu too) has a complete section on column allowables, and how to generate them (it's not that hard)

 

[rb1957]

looks like a 68ksi (fcy) steel ? (reverse calc'ing the Euler curve)

why would the welded section be twice as effective as non-welded ? ... heat-affected zone increasing the allowable ?, but wouldn't this benefit be localised to the weldment ?

i'll assume you know the euler equation.

the johnson curve, for short columns, is a parabola with a max. strength of fcy, and tangent to euler at 1/2*fcy

 

[Sparweb]

That chart is from Bruhn. Page C4.7. I wrote a FAQ on how to purchase a copy (see the Aircraft Forum).

There are "C" factors (end fixity) missing from the .GIF file you have.


Steven Fahey, CET