Designing a Steel Plate to act as a Corbel

[Eaglo]

Hello,

I'm having some trouble determining the strength of a steel plate to be used as a corbel. I don't have any good photographs or drawings for you, so I'll do my best to describe the thought.

How would I go about designing a steel plate to act as a corbel in support of a load connected to a column? Imagine the load applied to the end of the steel plate, and the steel plate is welded to the column.

If you could direct me to an example or a good place to look in the AISC I would greatly appreciate it.

 

[phamENG]

It's just a plate in bending and shear, and a pair of welds spaced the thickness of the plate taking shear from direct shear and out-of-plane moment.

You'd be better off using a stiffened seat, though, more likely. Search for "stiffened steel bearing seat" and you should get some AISC design examples. There are a few old threads on them on here.

 

[milkshakelake]

I don't know the application or loading you're looking for, but here's my detail of it for supporting brick:

For such small loads, I didn't calculate the gussets. Only the bending moment (plastic section modulus Z times Fy) and deflection of plate cantilevered out from the gussets. Technically, the plate will be in 2 way bending, but that will need an FEM analysis, which is too complicated for a brick support.

If it was for something substantial like supporting a "walking" column, the column itself will need to be checked for additional moment, as well as the gusset plates, welds, and column web/flange. And then maybe secondary things like overstrength factor...which is somewhat of a questionable thing, but something to think about.

 

[KootK]

What you're attempting is most commonly done with a seat angle as shown below. The setup is discussed in the AISC Steel Construction Manual, complete with tabulated capacities.

It's just a plate in bending and shear, and a pair of welds spaced the thickness of the plate taking shear from direct shear and out-of-plane moment

Do we feel that to be a street legal setup? I've always steered clear of it as it feels a bit to close to using fillet welds in bending about their longitudinal axes for my liking.

 

[phamENG]

street legal setup

When I was just a broke sailor that couldn't afford gas for my lifted Jeep anymore, I bought a beat up Mazda Protege for $360. I had to cut the back door open with an angle grinder, the shift lever bushing was shot so I had to really focus and remember what gear I was in, and the radiator was split open and steam constantly (but slowly) leaked from under the hood. It was street legal, but I wouldn't say it was a good idea to drive it...

 

[KootK]

Mmm.. the Protege. Those were fine steeds. Wicked reliable and kind of fun to drive in their own way. I'd probably still be driving mine except for the fact that my city experienced biblical flooding one strange year. My Protege floated away from my house while I was trapped at work and then got towed from whereever it wound up. I found her a month later at the impound lot but, by then, I'd already bought my father's Toyota Matrix. It hurt to leave her there.

 

[phamENG]

Love it. My clutch went out and I decided it wasn't worth it to replace it. I sold it to a scrapper for $500. There may have been tears.

 

[WinelandV]

On the topic of steel corbels, in Salmon an Johnson's Steel textbook, they have a great design section on seated connections, including stiffened seated connections.

On the off topic of Mazdas... I have an '08 Mazda 3 that I just had to replace the radiator in. My wife wants to sell it, but the 5-speed is making it difficult to sell.



Please note that is a "v" (as in Violin) not a "y".

 

[WesternJeb]

Blodgett's Design of Welded Structures also has a wonderful section on seated connections.