Concrete

[XM 2742]

I am in the middle of building a pole barn and one of the bays will be the spot for my new deuce. I am planning to pour a conctete pad for the deuce the question is..how thick. I was planning for six inches with more than normal rebar but was wondering what others recommend. Sure would like to avoid a cracked pad.

 

[muddog]

I was told by one of the contractors I work for to go with 6 inches, it would handle the weight of my 818.

 

[Recovry4x4]

In my humble opinion, you could safely go with 4" 4000 PSI with 6" depressed ends. My concrete guy swears by this and did the wings of my driveway like this. The 20,000# M108 doesn't phase it at all.

 

[Divemaster920]

6" would be fine for me. I would be more concerned about the sub-grade compaction. You can not keep concrete from cracking, but you do not want it to start sinking, thats when your slab starts to look bad. Rebar helps keep the concrete the same level when does crack. It also helps spread the stress so that it will not crack as much.
Compaction, compaction, compaction.

 

[goldneagle]

Use 6" 4500 PSI concrete with rebar and try to keep the slabs as close to square as economically possible. The more rectangular you make the slab the more chance it will crack. Compacting the ground below it helps a lot. I would also use some compacted crushed concrete under the slab. It is cheap to buy and will help support the weight.

 

[USAFSS-ColdWarrior]

Like us in San Angelo, TX (similar climate/soil conditions), your winter frost-line is virtually non-existant. A good compacted base (we'd use caliche here) and ground prep, adequate drainage, then the lighter specs mentioned above would be a minimum. If you want it over-designed for a better margin of safety, then thicken the slab.

Talk to a reputable LOCAL concrete contractor and ask him to "bid" the job and include his thickness recommendations for bid comparison... then YOU can always out-bid and DIY the project. (Or maybe get him to do it if the price is right and he'll stand behind his work with a guarantee.)

Just my

 

[jcappeljr]

6" with rebar is fine.

 

[rlwm211]

Just as in road building, the subbase is what holds the weight. If you have excess moisture in the subbase you can cause soft spots which will cause the slab to crack excessively.

I would make sure there is a deep layer of coarse gravel under the slab and make sure the area under the slab drains. Beyond that 4" of high strength concrete with adequate rebar will be more than enough to hold a "parked" truck. If you are planning on doing any heavy repair work on the slab including jacking and possibly "dropping" things onto the slab, the extra 2" of thickness might be desirable.

As was mentioned above, ask your contractor for his recommendations. If you can afford it, go with the 6" slab. Don't scrimp on rebar, especially at the entrance and/or exit.

As I mentioned, make sure proper subbase preparation is done, or else you will be doing it over again.

Just my two cents worth

RL

 

[tm america]

6 inches is plenty 4 would probably be fine for parking if you want to be able to put a lift in later i would do 6 and do mesh and rebar. plus the area just at the outsides of your tires i would do 8 inchs .but remember all concrete will crank at some point .thats why you use rebar to keep it from pulling apart.

 

[cundupa]

I have a 6" floor in my shop, steel fiber instead of re-bar. It's been over 10 years with no cracks. I run on it with my dozer, excavator (20 ton) Dump trucks and park a fully loaded M919 in there (35 ton). Most important thing is whats under it and COMPACTION! The cake is just as important as the frosting.

 

[clinto]

I am in the middle of building a pole barn and one of the bays will be the spot for my new deuce. I am planning to pour a conctete pad for the deuce the question is..how thick. I was planning for six inches with more than normal rebar but was wondering what others recommend. Sure would like to avoid a cracked pad.

Great discussion we had a while back about concrete and the Deuce:

http://www.steelsoldiers.com/deuce/1981-will-deuce-crack-damage-4-slab.html

 

[rlwm211]

So CLinto, what did you do to install the lift? Maybe this should be in the original thread, but it seems relevant here.

RL

 

[XM 2742]

Thanks guys...six inches it will be.

 

[southdave]

Subgrade is what is important. concrete is just a surface 4" is fine use fiber mesh to control cranking, control joints are very important, this depends on building layout and it dynamics. you can waste alot of money and time pouring 6" and rebar still end up with a cracked up floor. I pour this crap for 20yrs than got a BSCE, use 4000 psi concrete nonair entrianed . pay attendion to the opening where the truck comes and go thinckin these

 

[clinto]

So CLinto, what did you do to install the lift? Maybe this should be in the original thread, but it seems relevant here.

RL

The money has never shown up to build the shop-I am finishing up a carport until I can build it.

 

[glcaines]

Make sure you compact as much as you can and use gravel as the base, use plenty of re-bar, 4,000 - 4,500 psi concrete. Don't scrimp on any of the three and you will do fine.

I saw someone jacking up a truck once, and the jack punched a hole in 4-inch concrete, and it was undoubtedly a low PSI mix.

 

[4x4 Forever]

Six sack mix w/ 6" slump / Air entrained / 6" / 5/8 rebar around the edges / 6Ga Remesh in the field / Tie all together and pour your concrete

If sub base is good and firm, pour directly over it. If sub base is questionable scrap 4-6" off and spread 610 roadbase in and you can compact with a pick up or car. Just get in your rig and run over it and cover all the area. Another way to do it would be to set a sprinkler up over it and let it soak in, you just have to let the area dry before you pour, a few days (actually the better way).

Unless you are young and spry and have young and spry friends, get someone to pour it for you. I have done several over the years and you would not believe the work involved. You can save on the labour if you prep the area yourself and set up the batter boards.

Probably looking at $0.75 preped and $1.50 turnkey for labour for a slab, depending on your area. Conc is going for $100 to $110 a yard for the 6 sack mix, again depending on your area. Lowes.com has a good conc estimator although there are several you can find on the net - just fill in the length-width-depth and it will figure the conc needs for you. No matter what figure you come up with add 2 yards for a fudge factor, even the experts dont get it right.

Good Luck!

 

[Nonotagain]

I've got a friend that has worked in the business for over 30 years building commercial parking garages and road surfaces.

When I saw this post pop up I called Nick and asked, “Nick, how thick of concrete do I need to support a 20,00 vehicle in a residential garage?”

Nick said that 4000 psi concrete with #4 rebar, which is 1/2" rebar on 12" centers. Pour concrete 6" thick on bed of compacted stone base at least 4" thick.

Nick also indicated that adding fiberglass is good but not needed, though doesn’t add much to the final cost.

Don't go ape poop in over ordering concrete since most companies will charge you for any unused product and others won't take back the left over.

I built a 12x18' pad with footers for a large hot tub two years ago. The footers were three foot deep (32” frost line here in MD) and 16 inches wide, rebar re-enforced and a 4" bed of concrete. The woman I built this for didn't want to pay for the footers until I told her that they would not approve her permits since the hot tub was going to be enclosed. Her neighbor that was feeding her information on you don't need this or that had his enclosure collapse under the two feet of snow we just had while her enclosure shows no evidence of movement.

 

[Recovry4x4]

If you are going to order surplus readymix to make sure you get it done in one pour, Set up some extra forms for added little pours to use the overage. Maybe fill some 5 gallon buckets with an eye in the middle to use as anchors for whatever. I had a neighbor who would form sections of a carport for weeks at a time then one morning out of the blue, he would be out there finishing. When asked he had hooked up with some local drivers and if they had extra mix, they would drop it at his place and clean out right there. He did a 20X30 carport like this, one section at a time.

 

[4x4 Forever]

If you are going to order surplus readymix to make sure you get it done in one pour, Set up some extra forms for added little pours to use the overage. Maybe fill some 5 gallon buckets with an eye in the middle to use as anchors for whatever. I had a neighbor who would form sections of a carport for weeks at a time then one morning out of the blue, he would be out there finishing. When asked he had hooked up with some local drivers and if they had extra mix, they would drop it at his place and clean out right there. He did a 20X30 carport like this, one section at a time.

Setting up additional forms sounds good, I have had several customers do the same. Better than loosing the left over. I've seen some pretty neat things cast this way!

The carport project is pretty common, if someone refuses the load or the load is in the mixer too long, the conc companies look for a place to dump the stuff. The only bad thing about it is that YOU have to be ready to pour on THEIR timeframe. I had one fellow pour all of his footings like this for a 40x60 and then top coated it with the good stuff, saved about 10K as his footings were big enough to drive a deuce in (just kidding about the deuce, but 120yards of conc is $$$).

Id rather order more than needed than to have a truck bring me 2 yards at the last second, kinda expensive and the conc suppliers dont like to accomodate you all of the time. Especially when they are busy with a big project.