3-point concrete placer?

[ishiboo]

I am considering doing my driveway in concrete... but I've never done concrete before. I'd like to have the knowledge though. A good place to start seems to be a parking pad next to the barn.

One idea I had is creating a tool for placing concrete that I would pull behind the tractor. Basically, it would be fixed for the width, and be a simple rectangular box. It would have wheels on each side which would ride on the 2x4 or 2x6 forms. The concrete truck would place the concrete in this box, which would then be pulled forward, essentially handling the entire "distributing concrete" and screeding process. The rear board could even simply move back and forth to act as a true screed if necessary.

My feeling is this would allow 2 people plus the driver to essentially place the concrete, removing a ton of back-breaking work and leaving only the finishing process for manual labor.

What am I missing here? This seems like it would work, but it also seems too simple and cheap that someone else would have done it. There are some minor logistics issues, in this design the concrete truck would have to drive next to the rig, and there would need to be enough space between the rear of the tractor and the box to allow room for pulling the wire mesh up. But it seems doable.

 

[tjcarguy]

I've done a few concrete placements and I'm considering the same projects. I doubt a good truck driver will have any problems placing concrete just where you need it. Watching an experienced finisher work with a power screed and a power trowel is an worthwhile education . You can probably rent this equipement to DIY---Trevor

 

[bigtiller]

It sounds like a fun project for an experienced concrete guy, but only on a narrow, short sidewalk. That way you would be out maybe less than $500 just in case it failed. If it was my first time on something as wide as a parking pad, I'd volunteer to help the contractor I hired.

 

[CurlyDave]

I think that the weight of the box is going to cause the forms to fail. even a 2x4 or 2x6 placed on the ground will fall over when the weight of the box rolls over it.

The standard way to do this is to use the chute the truck has on it to place the concrete in the forms. This way they do not have to withstand any weight, only sideways forces from the concrete.

Set up the site so the truck can drive to within about 10' of any point in the concrete and you will be OK. You need to get a good book on DIY concrete, read it, and then watch someone do a pour. Come back when you have done that.

Screwing up a concrete pour does not mean that you are out the cost of the concrete and the other materials. It will almost always harden into an undesirable shape that must be removed. The removal is very expensive. You are out a whole lot more.

 

[Egon]

Best be looking for experience on the end of the chute and a couple of guys with the screed board. If the concrete is properly the screed fellows have very little or no work to do.

For a self levelling screed it gets difficult/expensive for a one time use. You'll need augers, vibratory system, rail/guide thingy and controls to operate it. Add in the concrete weight in the hopper and it gets substantial and expensive. Easier to spend the money on a crew. Probably cost a whole lot less than watching a segregated uneven pad set up while your trying to give it a trowel job and the next year watch the top spall off in large patches. The fellows that do concrete would be using a similar method to which you aspire if it worked easily and well.

 

[GLyford]

The only time I have ever seen something along those lines is when they pour lanes for highways and bridges, and that's not a simple "hook it up to a tractor", that's a large powerful purpose built machine. Traditional concrete is work, yes, but it's not that bad. As long as you have at least one other person there besides the driver who has done any of it before you'll probably be OK. Completely exhausted, but OK.

How wide and how long a driveway? Since they get poured in sections anayway, if you have more than just a couple of sections to do hire a full crew to do the first few, and only once you have seen the process and picked their brains and pushed the mud around yourself is when you should stop and rethink the process.

In my opinion, there is enough going on that you can fuss with a new machine OR you can manage a concrete pour, you can't do both...and that's if you have done it. Learn to do it a new way as you do it, with an untested machine? Not gonna happen. You're going to end up with a machine-reinforced concrete block, and you still won't have a driveway at the end of it.

Also, you're in frost country...proper finish is even more important if you want your driveway to last. Hiring a good crew might be worth it just to protect your investment in concrete.

 

[EddieWalker]

Concrete is one of those things that there are no shortcuts or ways to make it easier. It is VERY HEAVY, and unforgiving. It's simple in theory, but once you start working it, you realize that the timer is on and what you do once it's on the ground will dictate how it will look for all eternity. I've done a fair amount of work with it and I'm nowhere near close to being good at it. I've found that preparing the ground, setting the forms, digging out the footings and installing the rebar are what I can do well. If it's a small pour of just a yard or two, I can and will deal with spreading it and working it smooth. I've never done a job that was close to what the pro's do, but it's acceptable for those times when I do tackle it. For bigger jobs, I always hire a crew to spread and finish it. They make it look simple, but if you watch close, you will realize that the entire crew never stops moving and every single one of them is looking for and fixing things that you never even saw as a problem. It's one of those jobs that starts out hard, and then gets A LOT HARDER once the truck leaves.

Eddie

 

[BHD]

some years ago, I made a spin screed, http://www.tractorbynet.com/forums/build-yourself/332490-concrete-roller-screed.html#post4066215 it makes working the concrete much easer,

one can swing the chute and place the concrete fairly easily, the roller screed can help a lot, in seeing if it flat and if you have voids that need to be filled,

I had a vibrating screed that I made using years ago out of lawn mower engine that would clamp on to two 2x materials, and made a coupler of out side handles with c clamps and a rope, it was heavy, and the motor unreliable so I sold it,
also the vibrating screed would let mud work it way back up behind the screed, the roller screed has less of that problem,

 

[newbury]

OP -
What are the dimensions of your driveway?
I've got one that's about 10x20, I've got another that's about 100x20. About 40 years ago I had a truck pour about a 10 x 20 pad. I prepared everything myself and after the pour I finished it myself, no problem. I would not want to try a 100 x 20 myself.

Size matters.

 

[/pine]

Others have said about all that needs saying...but I have to say you answered your own question in the first post...

(nothing derogatory in any way intended)

What am I missing here?

I've never done concrete before.

My advice is to keep it as simple as possible and go with proven methods...

 

[MossRoad]

The first concrete job I tackled by myself was foundation walls for a garage. I rented a mini-tracked excavator, dug the trenches, set the footing forms and laid in the rebar. I had two people lined up to help me on pour day. We were going to wheelbarrow the concrete in by hand. Well, day arrives, concrete truck shows up, two helpers are no-shows and I'm standing there by myself with a truckload of concrete waiting to pour 112' of foot wide by 8" deep footing. Driver pours the first load into the wheelbarrow, I pick it up, get about 5' away and the handle snaps in half on the brand new wheelbarrow. $%&&%$%!!!!

Fortunately, the concrete driver realized I was an idiot and felt bad for me. He drove his truck THROUGH the piles of sand that came out of the trenches to get close enough to the footings to pour directly into them. I managed to get things leveled out and drop in the keyway in the footing by myself. I thanked that guy profusely for saving my $$$ as he would have had to dump the concrete. They can't take it back and use it later.

Anyhow, what I learned was:

A. Even if you read everything you possibly can and watch as many episodes of This Old House, Home Time, Holmes on Homes, etc... you will miss something very important.

B. To learn how to do concrete, let someone else teach you.

C. Start with small concrete jobs and move on to larger ones as your skills progress.

D. Concrete is HEAVY! (and permanent). :laughing:

E. Leave enough room for the concrete truck to get to the work. It didn't occur to me at the time that the dirt I dug out of the trenches would be in my way.

The things you learn by doing them wrong!!! :confused3:

 

[redman135]

I drive a concrete truck (6 wheeler) ie FULL SIZE , people say plenty of room,Yeah right, little car size room. In a straight line reverse I need 12" width minimum,(10' mirror to mirror), you always need to manuvere. I need a lot more for corners,20' plus, The nose will swing out a lot further than people think. And trim the bloody branches. Trucks are taller than most people think,and leaving my paint on your trees means I won't go that extra bit further. Trees also smash mirrors (very irrate driver),and we have to explain our carelessness.
Is the ground hard enough to carry a fully loaded truck (24 ton)? Towing us out is expensive.
Talk to a concrete crew as to what they need to make their job easier, ie water to wash gear ,wash area, (illegal to discharge concrete wash water directly into storm water drains, or water ways, blocks drains and kills fish)
Having worked with a concrete gang ,concrete is HEAVY and what few people understand is "the clock is ticking",the concrete is going "off" ready or not,AND getting the finish right is a learned skill.Noo preasure,yeah right.
Lastly at your level of inexperience I strongly recommend you pay for experts. When you get it wrong a driveway is something everyone can see, oops.
Start much smaller where finish is not so important, ie a garden mowing strip, small concrete area of about 1 or 2 square metres to learn on, and mistakes are not so visible.
I suggest you start by learning the earthworks,then learning concrete . There is a lot more going on than meets the eye.

 

[/pine]

I can't swear to this but I heard that "Murphy"...(the one that wrote the law)...did concrete work on the side...!

 

[Ed of all trades]

The only thing I can add is the concrete clock demands that you do things not only before it sets up but at the proper time. You can't finish it before it is ready or after its ready and my have to know how to read the clock. Trust me and all the others who know, on a job that big, hire a crew.

 

[ishiboo]

Thanks guys, all great advice. A friend of mine is a landscaper who has done a ton of concrete work including decorative, so I have help... just trying to make it easier on us

 

[jel1988]

I have placed and finished thousands of yards of concrete over the years, it take alot of experience to get it right. Contrary to common terminology you place concrete only very specialized mixes actually pour. Concrete can be thought of like epoxy once you add the catalyst (water) the hydrating process has begun and nothing can change that fact. You have a certain amount of time to get the truck to site, discharge the concrete into the forms, screed the concrete and float and trowel it. At different temperatures and humidity this reaction speeds up or slows down, certain admixtures can modify this reaction. In your area you should add aer ( helps concrete deal with expansion and contraction associated with freeze thaw cycles) the concrete can be retarded ( the set delayed ). So even if you and your buddy are working a different day the mix can vary signicantly. Concrete will crack, you can't stop it only try and contol it. If your driveway is 20' wide I would work in 20' long sections ( I would cut it into 10' * 10' squares a few days later) this would be a manageable size for a 2 man crew. The most important job is the base. The further north you live the deeper you must prepare the ground. Here in SC they place the concrete right on the native sand, where I live (north of lake Huron ) minimum driveway preparation is 12" of gravel. If I were you I'd prepare the ground (1 foot wide than the driveway on both sides) and call the pros, they get it right everytime.
PS Here in coastal SC they only charge about $4 sq/ft for flatwork.