Concrete slab question General Building and Construction Discuss Concrete slab question in the General forums; is there anyone under that slab ??? Looks good man... only how many to go till you get to the ...

[ThisOldGarageNJ]

is there anyone under that slab ??? Looks good man... only how many to go till you get to the oven ??

Nice job
Cheers
Mark

[Archena]

Originally Posted by ThisOldGarageNJ

is there anyone under that slab ??? Looks good man... only how many to go till you get to the oven ??

Nice job
Cheers
Mark

Hmmmm, ya know, I haven't seen RT all day...



Congrats on the purdy concrete, FX!

[RTflorida]

Hey now!!!
Although that was well deserved and Jimmy Hoffa WAS like a father to me, I wouldn't be caught dead (pun totally intended) wearing a pair of cement shoes after Labor Day.

RT

[ThisOldGarageNJ]

We all know "jimmy" will be at the Giants game today

Cheers
Mark

[Archena]

Ouch! Too bad FX didn't bury those puns while he was at it...

[fxpose]

...lol...

I did toss in a few items though... some dated junk mail and a few empty diet soda cans.

[fxpose]

Moving on to the next area, if I decide to suspend this 8' x 12' slab, should it rest on all four sides? Having only an 8' span can it just suspend end to end with nothing supporting its sides or mid-span areas? Should I erect block columns or a 12' wall across?
I'm not sure what would be the best approach here. Of course, I can always use fill instead.

[Archena]

Needs more support. Needs to be anchored on the building side - don't just use the building. Most wooden decks fail because they are only lightly supported on the building side. Great "America's Stupidest Videos" fodder but not a great homeowners day. Concrete would only exacerbate the problem so think new footings.

Not sure about the span but I'd err on the side of paranoia and add additional footings. By the way, how deep is it going to be?

[fxpose]

Originally Posted by Archena

Needs more support. Needs to be anchored on the building side - don't just use the building. Most wooden decks fail because they are only lightly supported on the building side. Great "America's Stupidest Videos" fodder but not a great homeowners day. Concrete would only exacerbate the problem so think new footings.

Not sure about the span but I'd err on the side of paranoia and add additional footings. By the way, how deep is it going to be?

It's this area to the right. It will only be under three feet high at its highest point.

[ThisOldGarageNJ]

hey fx,,,
my thoughts,,,
do not attach it to the existing foudation... too much opprotunity for settling..
you will definitely need and expansion joint or two....
I would rather see you fill this one as it is a big span, Or perhaps you could put a double column of cinderblock (with a footing) or sonotubes, thru the midpoint to receive some of the load... as well as the sides..

Concrete Slab Calculator - The Concrete Networkthis is just a calculator for cement.....

Reinforcing Concrete
While concrete has tremendous compressive strength (load bearing) it has poor flexural and tensile strengths. In most small concrete slab construction this is not a factor. However, if you are installing a patio size slab or a slab that will be supporting an unequal weight load, it may be necessary to use steel reinforcing wire. Reinforcing wire is available in rolls. Place the wire in the area that is to be filled with concrete. Support the wire off of the ground using metal stakes or rocks. It is important that the mesh is embedded between concrete on all sides.

okay this one might be good but it had me kinda lost....Design and analysis of reinforced concrete column calculator

I think this one might help you.....Reinforced concrete beam and 1-way slab calculator

Hope all this mumbo jumbo helps
Mark