topic Re: Warping Constant using AISC member in Robot Structural Analysis Forum

Warping Constant using AISC member

CameronEC — Wed, 06 Feb 2013 23:15:42 GMT

AISC members have a warping constant (Iom or Cw) = 0 using the member from the AISC database. (see below).

But when I use this member with the CSA S16-09 design code, I get results that assign a value to Cw (see below)

Where is ROBOT getting the value of Cw?

Thanks,

Re: Warping Constant using AISC member

Artur.Kosakowski — Thu, 07 Feb 2013 10:25:03 GMT

It is calculated 'inside' the steel design module either based on formulas form the selected design code or the general ones for the declared section type. E.g.

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Re: Warping Constant using AISC member

Anonymous — Thu, 07 Feb 2013 09:58:56 GMT

Artur,

This answer is also useful for my last post on Lateral Bucklyng of Tapered Section.

Re: Warping Constant using AISC member

Anonymous — Mon, 18 Jan 2016 07:06:43 GMT

Hello!

Is there an calculation formula how to calculate Iw for rectalngular cross section? I find for all cross sections except rectangular.

Re: Warping Constant using AISC member

Artur.Kosakowski — Mon, 18 Jan 2016 16:37:49 GMT

alpha=b-t

beta=h-t

Iw=alpha*alpha*beta*beta*(alpha-beta)*(alpha-beta)*t/(24.0*(alpha+beta))

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Re: Warping Constant using AISC member

Anonymous — Tue, 09 Jan 2018 23:58:31 GMT

Artur.Kosakowski, Would you please provide the reference of that table? Thanks.

Re: Warping Constant using AISC member

Artur.Kosakowski — Wed, 10 Jan 2018 10:04:00 GMT

Hi @Anonymous

It is from the Polish steel design code.

Re: Warping Constant using AISC member

Anonymous — Wed, 10 Jan 2018 14:42:28 GMT

Thank you, @Artur.Kosakowski !

Re: Warping Constant using AISC member

Anonymous — Mon, 07 Oct 2019 09:27:09 GMT

I was trying to get a consistent method to calculate the warping constant (Cw) of closed sections and I wanted to compare it with an analytic formula. Could you tell me what is the source of the one you published here? It's easy to find warping constant formulas for open sections, not so much for closed ones. Thanks in advance.