Go to Bruhn on page C5.7 and use figure C5.13.
With edge rotation simple means that the curve can be used for SS, clamped, and mixed edge conditions.
To determine n accurately use equation (4) on page B1.8
and take a stress strain curve of your material and draw two curves on it. 1)...
1) Crippling is crippling - first the flanges buckle and then the web (or vice versa) and then the section cripples.
2) For a quick estimate of the crippling stress use equations C7.16 and C7.17 in Bruhn on page C7.11 with 1.9 replaced with 1.7. Once you have the effective lengths multiply them...
I think I am prepared to answer the question of what effective width to use for inter-rivet buckling in order to calculate the load the skin is carrying when the skin buckles.
Fir must be less than or equal to Fcy
From Bruhn on page C7.10 equation C7.15 for a continuous sheet reads
w1 = 1.7 *...
I made an FEM model which checked well with SS but not clamped.
The ratio between the two methods is ~3 not 1.18
Only two edges - top and bottom are clamped.
I'mm not to happy with the results.
thread2-110541
The sugesstion to use 2b (where b is the rivet spacing) for the effective width is an excellent one, but do not use this width with the standard inter-rivet buckling stress found in various sources such as Bruhn. I think the difference is about 18% with Timoshenko being higher...
