crushed concrete under slab?

[chadman]

I need a lot of fill to bring my new building up to grade. Stone will run me about $18 per ton delivered. A local concrete outfit has a bunch of old concrete and a stone crusher. They said they can do crushed concrete for $10 per ton delivered. Is there any potential issues with using this in lieu of the stone?

 

[mrpowderkeg]

It's about the best thing ever! how much do you have to bring it up? We use to use it under roads in a particular area that had underground springs, we would dig out 2 feet of earth from the previous road, lay nylon fabric and fill with crushed concrete to provide a base for the new road. Nothing else worked. It's almost like it sort of "sets". We have it on our construction lot instead of gravel. about 3 feet of it. after being driven over for years, even digging in the lot is a grueling task with a backhoe. You need to rip it with a dozer.

 

[Big-Foot]

As long as it has been compacted, I would believe it to be just fine..

 

[JimVonBaden]

That is what I used for my patio and driveway!

Jim

 

[ddawg16]

I don't see how you could do better.....

About the only added thing....maybe rent a compactor and stomp it down real good....but if what they give you looks like the stuff Jim has in his pic.....I don't see how you could have any issues.

See....recycling does have advantages....

 

[Jeffksf]

Absolutly it's fine for base, It's ODOT approved for alot of applications in Ohio. I'm sore other states DOT's have it approved as well.

 

[RVDan]

Considering its at least 70% aggregate, there's no reason not to use it

 

[HOTFR8]

As long as you can compact it well I see no difference with crushed concrete to crushed rock.

 

[rsanter]

You have to compact it to make a good base layer

Bob

 

[1jjpop]

Add water before you use tamper , pick up a handfull and make a ball out of it with your hands , you can tell if moisture is right. it should compact.

 

[Big-Foot]

I think somebody should mention compacting it...

 

[White 99]

Some of it is kind of dirty with glass, tile and other things. May also have some metal left in it. I have some on my road I wish I would just have gotten good stuff. If it will be covered it wouldn't show anyway.

 

[jhelrey]

Dump in 2-3 inches worth depending on how large of a plate compactor you have. Lightly wetten and pack. Repeat process until at grade. If you have a corner that is low, start there first and work your way level. Plate compactors work best when 100% level.

 

[Vet65te]

Can someone tell me the difference between crushed concrete and what I've heard is called 'AB', which I guess is aggragate base? The lot we intend to build on in Prescott Arizona is going to have a long driveway and a fair slope from the access road out front so the intention is to use concrete for the sloped area and again for the pad in front of the garage but we've been told that the underlying base, known as AB, can be used for the flat area between the garage pad and front entrance slope. This AB I believe is what is used under the concrete anyway. Any benefit one way or the other to substitute crushed concrete instead of this AB? By the way, not even sure if crushed concrete is available in that region.
Thanks,
Mike T.

 

[JimVonBaden]

Crushed concrete isn't as good as other specific rock that is comonly used for driveways. It is dirty and unevenly crushed. It does make a good base for other top material, so long as it is properly compacted.

Jim

 

[Vet65te]

Jim, thanks for the info, it's appreciated. Looks like I might stick with the 'AB' for those flat areas of the 'long' driveway, unless someone has a better suggestion.
Mike T.

 

[RobSmith]

Is there a coal fired power station nearby ? They produce an ash that is excellent road base or fill. It's cheap too.

 

[bigfootok]

All batch plants will stockpile "pump out". The leftover mud from a truck that returns with a partial load.

They simply dump the concrete on the ground, spread it out and let it dry.

I had a 45 X 60 garage apron that had 7 feet of elevation change from one end to the other. We built a concrete retaining wall and proceeded to fill the area with 30 loads of "recycled concrete" from a local concrete batch plant.

I filled the area using 6-8 inch lifts, I then would soak the area with water and compact it using a 84" Padfoot Roller that weighed 25,000lbs.

Two years later I have one small crack.

I paid $50 per dump truck load which is about 13-15 tons. About $3.50 per ton.

Most of the batch plants will give this stuff away. All you have to pay for is the hauling.

I lived 11 miles from the batch plants. I paid a dump truck contractor $75/hour per truck and they were able to haul 1.5 loads per hour.

 

[bigfootok]

Don't confuse crushed concrete with the pump out I am speaking of.

The pump out is dumped on the ground let dry and then pushed into large piles.

Most demolition companies recycle concrete via crushing it and selling it as aggregate.

It is good stuff and works very well if you have a soft spot on a gravel road.

 

[Apostle66]

Concrete is a real good base we use it alot in driveways,plus recycling is good practice.

 

[hidollartoys]

DOT uses it as "road base" here.