Vulcraft composite VL deck vs shear studs
Vulcraft composite VL deck vs shear studs
(OP)
Hello,
I have successfully used Vulcraft 2VL & 2VLI composite decks over steel joists for floor framing systems over the past 10years. One of my colleagues is saying it's better to use shear studs on steel beams instead. Personally, I feel like it will be expensive to weld the studs for two to three story buildings. Can we just use Vulcraft VL composite deck on steel beams provided that we specify the puddle welds? I've always felt like using the composite deck (VL or VLI) with specific puddle welds is enough for partial composite action after checking the requirements.
Note, my floors are always 5.5" total thickness.
Thanks.
I have successfully used Vulcraft 2VL & 2VLI composite decks over steel joists for floor framing systems over the past 10years. One of my colleagues is saying it's better to use shear studs on steel beams instead. Personally, I feel like it will be expensive to weld the studs for two to three story buildings. Can we just use Vulcraft VL composite deck on steel beams provided that we specify the puddle welds? I've always felt like using the composite deck (VL or VLI) with specific puddle welds is enough for partial composite action after checking the requirements.
Note, my floors are always 5.5" total thickness.
Thanks.






RE: Vulcraft composite VL deck vs shear studs
RE: Vulcraft composite VL deck vs shear studs
RE: Vulcraft composite VL deck vs shear studs
RE: Vulcraft composite VL deck vs shear studs
Don't be afraid of shear studs. I can only speak to the areas I've worked, but composite steel construction is THE preferred and most common method for steel buildings. You need a detail that explains how the shear studs should be laid out, and then it is something the contractor should be able to easily handle.
Are you saying that you use concrete on steel deck supported by open-web steel joists as your default floor framing system? I acknowledge that there are certain applications a system like that makes sense, but that would be unusual to use all the time.
RE: Vulcraft composite VL deck vs shear studs
I have designed composite floor system in the past (some 15 years ago in Houston-Austin area) before I joined this small local firm (in a small city in Wyoming). The contractors here always ask us to find alternatives to our design to fit their knowledge, which is fine with me because the construction cost is reasonable. I was telling my new colleague that I don't see any difference in using composite deck on steel joists vs. on steel beams provided that I am not designing composite floor systems.
Also, our firm work on buildings between 2 to 3-story.
RE: Vulcraft composite VL deck vs shear studs
What makes the Vulcraft deck "composite" is that it has interacting lugs that allow it to engage the concrete so that the deck and concrete act together. But getting the beam and concrete to act together requires shear studs.
RE: Vulcraft composite VL deck vs shear studs
RE: Vulcraft composite VL deck vs shear studs
One thing to be aware of, though, with steel-concrete composite systems is that they can be particularly susceptible to vibration. I think that's a function of how thin the slab can be made to be. It's something to watch out for.
RE: Vulcraft composite VL deck vs shear studs
The savings comes in that the beam supports the wet mud and a construction load of about 20 psf, preferably unshored, but the presence of the studs supports the additional live load with no more steel.
Mike McCann
MMC Engineering
RE: Vulcraft composite VL deck vs shear studs
RE: Vulcraft composite VL deck vs shear studs
RE: Vulcraft composite VL deck vs shear studs
You said "to burn holes for the studs"... Really a non-issue here...
In that the studs are always welded to the steel beams at the bottom of the flutes in the deck, and the stud gun welds through the deck to the steel beam below, no cutting of the deck is needed. It is an automatic process.
Mike McCann
MMC Engineering
RE: Vulcraft composite VL deck vs shear studs
RE: Vulcraft composite VL deck vs shear studs
I'm not sure that any of these systems has gotten all that much traction in the industry. So, my guess is that there must be SOME reason for that. Maybe they don't offer great cost savings, maybe they don't perform as well as promised, or maybe they're just a pain to work with (for either the engineer or the contractor).
Personally, I'm keeping my eye out on these systems as they would seem to be quite promising. I just would like to get more feedback (positive or negative) from more engineers that are using them.
RE: Vulcraft composite VL deck vs shear studs
@Steelion, so you are saying if the studs are 12" O.C. you are saving 10 PLF in beam weight?
RE: Vulcraft composite VL deck vs shear studs
Example: 30 foot span:
Non-composite: W18x35 required. Weight = 35PLF X 30 FT = 1050#
Composite: W16x26 with 14 studs required. Equivalent Weight = 26PLF X 30 FT + 14 STUDS X 10 LB/STUD = 920#.
RE: Vulcraft composite VL deck vs shear studs
The building I am talking is 3-story office building, each floor has about 6,000 sq.ft. Since the contractors that always work on our projects have never seen us designed composite floor systems, I think i would rather use the composite deck on steel beams. With this I can still get the 1H fire rated the architect requires.
Thanks.
RE: Vulcraft composite VL deck vs shear studs
RE: Vulcraft composite VL deck vs shear studs
I agree with Steellion’s approach too. If the conc. is already there, why not use it to your advantage, assuming it is cost effective. Why not talk to a couple of your local contractor friends and see what they would think of the idea of shooting studs from above, and through the deck? Bring them some of the appropriate stud welding literature, and explain the potential advantages. What do they think their costs and difficulties would be, could you save enough steel, in the beams to make up for their extra costs? And, of course, your extra fee and extra effort should be included in that cost and serviceability study. There isn’t anything wrong with stretching the capabilities of your contractors, particularly when you make them part of that process. Just don’t spring it on them, if they’ve never done it before. That would just fulfill your negative prophecy.
RE: Vulcraft composite VL deck vs shear studs
This current project goes out at the end of the month, so i will use non-composite for it in the meantime.
RE: Vulcraft composite VL deck vs shear studs
The greatest trick that bond stress ever pulled was convincing the world it didn't exist.
RE: Vulcraft composite VL deck vs shear studs
RE: Vulcraft composite VL deck vs shear studs
If height is not an issue and the project is small, why not investigate an open-web steel joist system? We usually use joists spaced at 2'-6" o.c. with 9/16" form deck that supports a 3-1/2" to 4-1/2" thick slab.