Anchorage for Steel Framed Podium

[Pers Eng]

Have a client/owner who is looking to construct a 3 story wood framed structure on podium using concrete filled metal deck on steel framing instead of the more typical cast-in-place concrete construction. I am concerned about anchorage of the shear walls to the steel framing with a thinner slab that what would we would use for flat plate construction. I am considering welding threaded rods to the WF beams after the metal deck is in place prior to pouring the elevated slab but would be interested in any advise or experience anyone has. Building is on east coast so low seismic forces, wind will control lateral design.

 

[JAE]

One big issue with welding threaded rods is getting the welder to properly position the rod exactly where the hold down will be. Tough to do in the field without some significant efforts at layout control.

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[Pers Eng]

That was exactly my concern. The owner, who in this case is the builder also, has indicated he understands the potential layout issues, but you know how it is. In the field it will become my problem not his when things don't line up.

 

[JAE]

You might draw up a "fix" detail that would apply when the rods don't line up - showing concrete removal, re-welding of a new rod, and concrete replacement.

Just so he's clear on the amount of work required if they need to correct a "few".

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[structSU10]

For a similar condition, we provided a stub off the beam that had a steel plate set flush with top of slab. It was slightly bigger than the footprint of the studpack plus hold down, and allowed for a rod to be field welded to it once location was determined. It all went OK in the field, and we kept the shear wall slightly smaller than the length of the wall to allow some tolerance longitudinally.

 

[Shotzie]

Something like this may work well, similar to structSU10's suggestion Link

 

[hokie66]

Just use the metal deck as form deck, and build your slab of required thickness on that.

 

[humanengr]

Vulcraft decking manual (or similar decking manual) will provide data that can be used to determine required fastening
of the deck to the steel beam in order to transfer the required shear from the deck to the beam. Fastening may be welding or screws.
Shear studs could be used as well.