Steel columns with (2) anchor bolts 1

[Rdar43]

I've been working on several wood podium buildings that ends up needing steel columns due to the loads. If it's a 1 story column, I can meet the OSHA requirements allowing me to use (2) bolts and easily hide the base plate within the stud wall. Now I need a (2) story column and it's exceeds the 300lb self weight requirement and requires a (4) bolt condition.

My initial thought was to splice the steel column at the 1st floor, satisfying the 300lb requirement, and then installing the remainder of the column after the wood framing is bracing the column.

Does anyone know if this would satisfy the requirement or if there is an easier way to work around it? The architect on the project can't have the plate wider than 5.5" or else it will stick out of the wall.

 

[jayrod12]

Could they form a pocket in the concrete on the main floor to hide a larger baseplate?

 

[Rdar43]

That could be an option but on several past projects the G.C. and concrete sub aren't coordinated and forget to install the steel plates prior to pouring which just brings the problem back around in an RFI

 

[hokie66]

A good example of a silly government requirement leading to unintended consequences. Instead of using one column, you want to use twice as many, with likely twice the hazard.

 

[le99]

I think your proposed solution satisfies the OSHA requirement, however, you need to make sure the column is securely supported throughout the construction prior to being fully encased, or until completion.

 

[JoshPlumSE]

This is an erection issue, right? So, why not ask the contractor. I have a feeling all they'll have to do is add some temporary external bracing to the column during the erection phase. That might be less expensive than your solution.

Alternatively, you can also add a shallow "grout pocket" in the slab/ foundation at that level so that a 4 bolt anchor bolt base plate arrangement won't be an issue.

 

[DayRooster]

If everyone is okay with some field welding then you could do embed plates with field fillet welds. Takes some coordination but that’s another option too.

As for the OSHA problem about the two story sliced column…it’s hard to say. So much of the OSHA requirements can be up to interpretation of the OSHA authority. I have contacted them to ask them directly in the past if I feel like I’m riding the line. But be prepared for them to default to the no answer if they are unsure. Otherwise you could push forward with your judgment; just be prepared to have to defend your position as to while your situation doesn’t apply if it’s flagged or an OSHA recordable occurs.

 

[dik]

In Canada, we have (CSA S16):

I often encounter base plates with only 2, and have the following note:

-BASE PLATES HAVE TWO ANCHORS. CONTRACTOR TO TAKE EXCEPTIONAL CARE TO MAINTAIN STABILITY OF ALL STEEL FRAMING.

I don't know if it's a 'real workaround', but it seems to work (aka, I've not been challenged)...

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Do you feel any better?

-Dik