Warping constant (Cw) of cellular beams
Warping constant (Cw) of cellular beams
(OP)
I am quite unfamiliar with cellular beams and I am looking for a way in which to calculate the warping torsion constant Cw.
I am aware that for symmetrical I and H sections the following formula can be applied:
Cw = (Iy.h^2)/4
Can this be adapted to accommodate the cross section of a cellular beam?
I am aware that for symmetrical I and H sections the following formula can be applied:
Cw = (Iy.h^2)/4
Can this be adapted to accommodate the cross section of a cellular beam?






RE: Warping constant (Cw) of cellular beams
BA
RE: Warping constant (Cw) of cellular beams
I'm fairly confident that BAretired is correct for all standard pipes and tube that AISC uses. But, I'm just not sure about the odd mult-celled cross sections that you get in other fields.
RE: Warping constant (Cw) of cellular beams
BA
RE: Warping constant (Cw) of cellular beams
I'm looking for a method to calculate this constant without the use of software if possible.
Any suggestions regarding useful literature would be much appreciated as well.
RE: Warping constant (Cw) of cellular beams
I believe a "cellular" beam is the same as a castellated beam
RE: Warping constant (Cw) of cellular beams
RE: Warping constant (Cw) of cellular beams
Michael.
Timing has a lot to do with the outcome of a rain dance.
RE: Warping constant (Cw) of cellular beams
The only difference I can think between Castellated and Cellular is Castellated are cut and welded from one beam where Cellular maybe simply a beam with holes cut in the web with no welding as seen in a Castellated beam.....just guessing here.
RE: Warping constant (Cw) of cellular beams
Cw = tfh2b3/24
Since this expression does not involve web thickness, it seems to me that Cw is the same for a castellated beam.
BA
RE: Warping constant (Cw) of cellular beams
I was thinking the same thing, but haven't had a chance to look it up.
RE: Warping constant (Cw) of cellular beams
I have never calculated Cw for a castellated beam, but it seems to make sense that it should be the same as for a WF, H or I section. The top flange bends in one direction while the bottom flange bends in the other when the section is exposed to torsion.
The web plays no role in warping, but it does contribute to torsional resistance and is included in the 'J' term.
BA
RE: Warping constant (Cw) of cellular beams
Makes sense to me.
RE: Warping constant (Cw) of cellular beams
Yes, one could say that Cellular beams are the modern version of Castellated beams - they are fabricated in much the same way (also by flame cutting and then welding). I think the Cellular beams are possibly easier to bend (done before welding) to form curved or precambered members.
For interest's sake, I've included a picture showing the cutting pattern.
RE: Warping constant (Cw) of cellular beams