OK to leave old floor as fill?

[BSE1956]

Replacing a garage floor that has been compromised/undermined by Sandy.
There is a large void of up to 12" under most of the floor.
In addition to using crushed concrete and gravel fill, is is OK to just use the of pieces of the floor as part of the base?
The fill will be dropped in and then compacted with a large flat ********.

Thanks!

 

[NUTTSGT]

If there is a void under the floor, no the floor needs to be taken out to fill the void.

Reading your post again, I'm guess that it what is being done.


I'd have no problem using the broken up floor as fill as long as it doesn't create more smaller voids. Depending on how big the broken concrete is, it may need to be mixed in with smaller fill to close up the air spaces.

 

[rieferman]

I'm not sure, but is this a situation where a "mud jacking" type of solution would work? I'm just asking as I'm not sure when this is a good option or not...

 

[paulrey27]

If there is a void under the floor, no the floor needs to be taken out to fill the void.

Reading your post again, I'm guess that it what is being done.


I'd have no problem using the broken up floor as fill as long as it doesn't create more smaller voids. Depending on how big the broken concrete is, it may need to be mixed in with smaller fill to close up the air spaces.

Echoing what NUTTSGT said. The old floor as fill is great as long as you can be certain you aren't creating voids. Is it possible to 1) use a smaller aggregate when pouring a new slab? and 2) where you might suspect there be voids, use a ******** to ensure concrete has fill all possible voids?
Just my $0.02...

 

[Highbeam]

The more you break up the old slab, the better. Get a jack hammer and rubbelize it, then leave it as fill.

 

[joe49]

Replacing a garage floor that has been compromised/undermined by Sandy.
There is a large void of up to 12" under most of the floor.
In addition to using crushed concrete and gravel fill, is is OK to just use the of pieces of the floor as part of the base?
The fill will be dropped in and then compacted with a large flat ********.

Thanks!

Yes you can but you need to break it too at least 5 inch minus.