Metal deck closure - shop welded or field welded

[canwesteng]

A fabricator is trying to get me to accept shipping bent plate metal deck closure as field welded - is this typical? I've always had these shop welded but usually only small scale stuff. Only ever worked in industrial. so I'm sure what would be typical for say large concrete floors in commercial (this is still an industrial project, just with a lot of metal deck/concrete floor). Also, how is puddle welding the deck to the beams below normally handled? Just leaving top flange of beams uncoated? Will probably swap puddle welds for screws but just curious.

 

[Ron]

Puddle welds burn through the paint. Top flange can be left uncoated but usually not done as it's better to provide the coating than to worry about the small area burnt off by weld. I'm not a fan of deck closures. I prefer a perimeter angle that closes the end, provides added support and sets the screed for the concrete.

 

[dik]

It's my experience that closure strips and screed strips are field welded. I've even encountered 'funny' CFS closure and screed stips bent as a single unit with numerous bends to achieve the purpose. The contractor was sheets of deck bundled together for placing without worrying about having a few 'odd' items either separate or part of the shipment. The puddle welds are touched up with a zinc rich primer; they would not hot dip the sheets with the closure/screed attached.

About the only time I use mechanical fasteners is if there is a special coating, like for food processing, labs, etc.

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

-Dik

 

[canwesteng]

I guess terminology error on my end - these are bent plate welded to the steel, not the deck. I'm calling them closure plates but it's more a perimeter angle.

 

[dik]

are they going down to keep the concrete from entering below the deck, or are they going up to form the top edge of the slab... the difference between closure strips and screed strips. They have 'foam' fillers that fit into the deck flutes to keep the concrete from flowing into that space (leaking out?). I don't know what they are called.

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

-Dik

 

[canwesteng]

Going up to form the edge of the slab

 

[jittles]

In my experience with hot rolled steel bent plate perimeter angles, typically shop welded.

If there are tight tolerances or something strange like a radius to the edge, then I have seen them field welded to allow more accurate deck edge locations. Maybe 2 times out of dozens of projects have I seen field welded bent plates.