2005 ASD - Weak Axis Bending
2005 ASD - Weak Axis Bending
(OP)
I am checking some calculations....
I'm coming across something that just doesn't seem right while checking combined stress on a very large wideflange shape...W40x397
in looking at Eqn. F6-1 (2005 ASD) Mn=FyZy < 1.6FySY
I get an available moment of (50ksi x 300 in3)/1.67 = 8,982 k-in.
This is less than (1.6FySy)/1.67 so it controls.
The reason it seems incorrect is this would equate to a bending stress of 8,982 k-in/ Sy=191 in3 = 47 ksi.
this seems unreasonably high; near yield.
What I am missing here?
I also am inclined to only use Zy for the top flange for the loading, but that is another matter I suppose.
I'm coming across something that just doesn't seem right while checking combined stress on a very large wideflange shape...W40x397
in looking at Eqn. F6-1 (2005 ASD) Mn=FyZy < 1.6FySY
I get an available moment of (50ksi x 300 in3)/1.67 = 8,982 k-in.
This is less than (1.6FySy)/1.67 so it controls.
The reason it seems incorrect is this would equate to a bending stress of 8,982 k-in/ Sy=191 in3 = 47 ksi.
this seems unreasonably high; near yield.
What I am missing here?
I also am inclined to only use Zy for the top flange for the loading, but that is another matter I suppose.






RE: 2005 ASD - Weak Axis Bending
RE: 2005 ASD - Weak Axis Bending
Thanks for the sanity check Nutte
RE: 2005 ASD - Weak Axis Bending
RE: 2005 ASD - Weak Axis Bending
RE: 2005 ASD - Weak Axis Bending
My original thought was to still use F6 with adjusted Zy...
Thanks Nutte.
RE: 2005 ASD - Weak Axis Bending
RE: 2005 ASD - Weak Axis Bending
EIT
RE: 2005 ASD - Weak Axis Bending
Its a crane runway girder....not my design.
RE: 2005 ASD - Weak Axis Bending
RE: 2005 ASD - Weak Axis Bending
yeah I'm a noob.
EIT
RE: 2005 ASD - Weak Axis Bending
But, after working for some time now in industrial applications, it's become almost routine. I have worked on buildings that had girders 14 ft deep and spanned 120 ft.
I have worked on Boiler buildings for power plants that had trusses 28ft deep supporting the hanging boiler (top steel as the industry calls it).
Its good to be excited about it.
On the other hand, I'd love to design a W10 for a distributed load at this point!!!