Another concrete drive/slope project

[newbury]

At the house we bought in Mississippi there is a concrete driveway crossing a culvert leading up to the house. It had been widened and where it was widened it looks like they did not put down sufficient stabilizing base. And it is cracking and slumping on the "addition" (between the green lines).

It's about 100' long with a small culvert under it about where the red line is.
The side portion ranges from 3' at the far end to 5' at the near end.

I had figured it was going to be a tear out and replace with associated $$$$$.
I called a respected contractor out for an estimate. He gave an "off the top" of his head guesstimate of about $8K plus, perhaps ripping out old and putting down a new base

But he then proceeded to tell me that they could probably repair OVER the cracked section for significantly less by putting some mesh and a patch concrete down.

And then he proceeded to tell me I could probably do it myself for the cost of the patch concrete and mesh.

In the hazy past I'd done a lot of concrete mixing for building a house using a mixer. More recently I've done it in my FEL. So I feel up to the task of doing pours of concrete. But if I'm pouring concrete 1" thick x 100' x 4' it will take about 75 bags of QUIKRETE 60 Lb. Sand/Topping Mix at $5@. I know I need a mixer.

So I seem to be looking at an exercise opportunity (no need for gym fees!) for $<1,000 (w/ all cost including a mixer) or sit in a recliner and have someone else do the whole shebang for a heck of a lot more.

If need be I can dig up the old concrete, but if I can leave it there it would be easier.

So my questions for the forum:
What more info is needed?
What's the best way to tell if a "patch over solution" will work?
How thick can the said mix be used (I read for regular concrete it should be 2" or thicker, for the "patch" < 2")
Is there a better type of concrete?
What are suggestions for bank stabilization? Should I put down railroad ties? Rip-Rap? Should I pound in posts?
Any recommendations on small cement mixers? I can see a need for other future projects (including boots for some people).

All good suggestions welcome. Poor suggestions also expected.

I plan on building forms from my own timber, I've my tractor and backhoe available.

 

[bcp]

Some questions to think about:

Does it have to be that wide? Or can you go back to using the older solid part only? Maybe wider at the ends or turns only?

Would it maybe be better to go to an asphalt overlay instead of concrete?

Do you want to do it right, cheap, or good enough? And where on the line between "right" and "cheap" is "good enough?"

Bruce

 

[newbury]

Some questions to think about:

Does it have to be that wide? Or can you go back to using the older solid part only? Maybe wider at the ends or turns only?

I want to keep it that wide. If you look closely you can see I've flagged it at the crack of the old vs new, that's the portion we are using now.

Would it maybe be better to go to an asphalt overlay instead of concrete?

I don't like asphalt if I can have concrete.

Do you want to do it right, cheap, or good enough? And where on the line between "right" and "cheap" is "good enough?"

According to the contractor "right" is the method chosen, "cheap" would have been asphalt.

 

[rambler]

Without replacing the base as one unit that will settle together as one, the crack will always be there. Pouring more concrete over the tiop with mesh is probably a 5-10 year patch.

imho

--->Paul

 

[deezler]

A patch of new concrete is not going to match to color and texture that you already have, and will look kinda funky, IMO.

Concrete is definitely a more permanent driveway material, but you have to analyze that in the context of where you are applying it, too. Your driveway is a big, elevated berm. What is the underlying soil/ fill material like? Do you even know?

The reason the exisiting conrete expansion cracked and slumped off was, as you note, due to poor compaction or instability of the base. This is only going to continue. So, you throw on a new concrete "patch". How long do you expect it to stay level and flush?

As for berm stabilization. Well, those trees are probably very well rooted, and should be helping you. You don't want to hurt the trees (if they die, you're screwed). You could consider drilling post holes along the drive edge, well away form the tree trunks, put in posts and then anchor a retaining wall to that. Then remove the exisiting problem are of concrete, re-fill the base and compact the **** out of it. Then new crete should last a while.

 

[newbury]

A patch of new concrete is not going to match to color and texture that you already have, and will look kinda funky, IMO.

This is Mississippi, almost everything looks funky, we aren't the least concerned about color or texture match if it's a difference between $1000 and $5000.

Concrete is definitely a more permanent driveway material, but you have to analyze that in the context of where you are applying it, too. Your driveway is a big, elevated berm. What is the underlying soil/ fill material like? Do you even know?

We (the potential contractor and I) ASSumed that under the original was normal fill for a proper drive. The other section was probably done half-mule like many other things about the property.

The reason the exisiting conrete expansion cracked and slumped off was, as you note, due to poor compaction or instability of the base. This is only going to continue. So, you throw on a new concrete "patch". How long do you expect it to stay level and flush?

I don't know, that's why I'm asking. I'd expect it to not move for a few minutes if I did NOT stabilize the bank/berm.

As for berm stabilization. Well, those trees are probably very well rooted, and should be helping you. You don't want to hurt the trees (if they die, you're screwed). You could consider drilling post holes along the drive edge, well away form the tree trunks, put in posts and then anchor a retaining wall to that. Then remove the exisiting problem are of concrete, re-fill the base and compact the **** out of it. Then new crete should last a while.

Thanks, that's what I'm looking for.
Why drilling posts versus pounding in?
Any suggestions for a retaining wall?
Something like the Highway Department puts in?
Railroad ties?
Again thanks.

 

[deezler]

Sorry, I should have specified that I'm primarily internet-educated on these matters, and not so much direct personal experience (other than my own observation).

Why drill hole vs. pound in? Umm? Just seems more feasible. A good skid steer, 3-pt mounted, or even 2-man auger should be able to get 42 if not 48" below grade. If you have a means for efficient post pounding, you could do it starting at that depth.

Not really sure on retaining wall materials. highway barrier, or guard-rail, would probably work really well.

 

[newbury]

Well the project is still in the planning - but I just ran across this thread http://www.tractorbynet.com/forums/photos/95343-retaining-wall-unopened-sacks-concrete.html about using unopened bags of crete.

I had been thinking of renting a post driver and driving in railroad ties about every 4 feet, as bracing for a wall of railroad ties.

Now to get down to the figuring of the tradeoff between railroad ties, concrete bags, rip-rap or some combination.

Any further thoughts or suggestions?