Weak axis bending of A36 plate
Weak axis bending of A36 plate
(OP)
I have a 2"x14"x14" A36 plate that I want to analyze the stress of as it bends about the weak axis. I was taught that stress = moment/elastic section modulus,S (σ = M/S). When I look at F11.1 of AISC for yielding of rectangular bars, I see that Mn=Mp=FyZ >= 1.6My. I have determined that FyZ governs the design. My question is this: to find my actual stress, do I divide the moment by the plastic section modulus, Z (σ = M/Z)?
Thanks
Thanks






RE: Weak axis bending of A36 plate
RE: Weak axis bending of A36 plate
RE: Weak axis bending of A36 plate
RE: Weak axis bending of A36 plate
RE: Weak axis bending of A36 plate
RE: Weak axis bending of A36 plate
DaveAtkins
RE: Weak axis bending of A36 plate
RE: Weak axis bending of A36 plate
This will be difficult for me when I have to check a flexural member that also experiences torsion. In the past, I would check the actual stress caused from the flexure added to the stress from the torsion (AISC Design Guide 9) and compare that to allowable stress. On a past job, I actually used M/Z to find my bending stress then added the torsional stress to it and compared it to Fy/1.67. Is this wrong?
RE: Weak axis bending of A36 plate
RE: Weak axis bending of A36 plate
Combined torsion & other stresses should be analyzed using an allowable stress method per H4.3 (on open shapes).
RE: Weak axis bending of A36 plate
RE: Weak axis bending of A36 plate
In your case, I'd be inclined to revert to determining bending stress using M/S for the combined bending and torsion check (only) -- but that may just be me trying to be conservative and a little skittish around torsion. I'm curious to hear what the others will say there.
(Typing too slow, beat to the punch)