gusset plate connected to the column web. 1

[malikasal]

we know that if we connected a gusset plate to column flange longitudinally we have to check a couple of limit states such as local web yielding, local web crippling and so on, but what if the gusset was connected to the column web, the code doesn't have any criteria for checking this type of connections .

some might say we should check the web for bending but i think that is too imaginary.

So i am hoping to gather some opinions from the great minds out here??






ôIf you don't build your dream someone will hire you to help build theirs.ö

Tony A. Gaskins Jr.

 

[KootK]

some might say we should check the web for bending but i think that is too imaginary.

You do need to check the web for weak axis bending and, perhaps, a few other related failure modes. I'd recommend looking at the AISC recommendations for checking HSS side walls for various connection imposed loads. The concepts are very similar. The only reason to ignore bending loads in the web would be if you've design a connection where you are confident that all of the load delivered to the web will be purely shear. If there's a transverse component to the load, there ought to be a bending check of some sort.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[Hokie93]

The best reference I have seen on this topic is a paper ("A Membrane Method for Transversely Loaded Column Webs") by William Thornton. A very similar question was posed in the "Steel Interchange" feature of the July 2015 issue of Modern Steel Construction magazine. That article is available at:

http://msc.aisc.org/globalassets/modern-steel/archives/2015/07/si.pdf.

 

[KootK]

I tracked down the excellent paper that hokum reference. It can be had for free here: Link.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[malikasal]

thank you guys..
helpful stuff.



ôIf you don't build your dream someone will hire you to help build theirs.ö

Tony A. Gaskins Jr.

 

[Ron]

A gusset installed to the web of a column has a potentially significant point loading effect on the web and it should be checked. Fairly often it will not be critical, but there is a chance that it will be critical. Another approach that you can take rather than providing a typical triangular gusset attached to the middle of the web, is to double your gusset and move your gusset to the inside of the flange or provide a welded cant rather than a gusset along the web. In either case, check the calcs.

 

[nutte]

Hokie, that is a great article. Thank you for posting it. By the way, it can also be found for free on AISC's web site:

https://www.aisc.org/WorkArea/showcontent.aspx?id=3576

Table 2 in that document lists capacities realized in testing, and compares those to capacities realized by the equation developed in the paper. The ratio of tested capacity versus calculated capacity ranges from 1.33 (tested capacity higher than calculated capacity) to 0.69 (tested capacity lower than calculated capacity). The paper notes the overall statistical error is around 12%. But those low values, 0.69, 0.73, 0.76 give me pause. I'm surprised the paper doesn't address those low values, perhaps with an additional reduction on the calculated capacity.