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Re: Strength of Non-Compact HSS

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Hey, Davis, this brings up (again) a point that needs to be reiterated:

The Design Specification for HSS members is GREAT, in and of itself a good
reason to spring for the purchase of one of these manuals if you do much design
with HSS.

But it ONLY comes in the LRFD flavor, and as you point out, the methodology is
sufficiently unique to HSS that I don't believe you could "wing it" by applying
the AISC-ASD Design Specification to these members.

I haven't tried--I've only used the HSS Design Spec a few times, for column
design--but I'm sure someone could "convert" the HSS LRFD formulae to ASD, but
to me this was yet another nail in the ASD coffin. I'm surprised that no one
here has complained about this (that I can recall).

Davis Parsons wrote:
> The "Specification for the Design of Hollow Structural Sections (1997)
> should be followed for HSS members acting as beams. This spec has
> slightly different requirements than the LRFD spec. You will find that
> the limiting b/t ratios will control strength long before the unbraced
> lengths.
> For example, an HSS 8x8x3/8, Fy=46ksi has a b/t ratio of 19.9 which is
> less than the limiting value of 28.12.  ØMn is 101 ft-k, Lp=29.38 ft and
> Lr=533.61 ft.