Lightweight fill to raise composite floor elevation

[Galambos]

We have a floor space that will be designed for a 4" raised access floor on a composite beam floor system.

The Owner would like the option to eliminate the raised access floor after construction and add some sort of 4" concrete topping.

I'm thinking of lightweight concrete bonded to my concrete slab on metal deck, but wondered if there are other options out there.

Thanks!

 

[ishvaaag]

Some kind of lost formwork forming vaults

http://www.caviti.es/

 

[Den32]

Not 100% clear on this question?

When you say 'after construction' does that mean 10 years from now, or still during construction phase? How much floor area are we talking about (just a room, an entire floor, etc)?

4" bonded topping would work - will this floor be exposed? If so, pay attention to crack control, etc. in the new topping slab. I would use Fibers in mix and cut crack control joints on girder lines.

In floor structure design, be sure to account for the additional 4" thick concrete load (superimposed, POST composite load). I would assume normalweight concrete.......when they get a contractor in there to do the work 5 years from now, unless specifically told, they are just going to place the cheapest product (normalweight concrete). Lightweight is harder to pump too.

Unless I am missing something, I don't see how the 'forming vaults' relates to this question? Looks like a cool product though.

 

[ishvaaag]

Well, I have thought the question asked was most constructive than structural, means available to raise somewhat some level; here it is used normally at ground levels to form a cavity on a lost base of concrete, and even over mats to permit water flow to drains to pumps where it is thoght sometime such incidence might happen. I think from the question the structural aspects do not escape to whom is asking and so I interpreted the question this way.

 

[Galambos]

Thanks for the replies.

"After Construction" means 1 month to 1 year after the slab is placed.

The topping would be applied to the entire floor, which would be roughly 90ft x 200ft.

Right now, I am thinking 4" lightweight concrete with wire mesh.

Some ideas that have been thrown around include styrofoam w/ concrete topping, but i dont have a comfort level with that.

 

[steellion]

Plan for the weight of 4" of lightweight concrete, then if they decide to go another route, you're covered. I would only consider the extra concrete to be dead load, I wouldn't consider it to be adding strength as part of the composite floor system.