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Fuzzydog

Red Skull Member
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May 20, 2020
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BC Interior
share your wisdom/experience

I am tired of rolling around in the dirt to work on my junk, my friend's junk and my daughter's junk so it is time for a concrete driveway.
I have excavated 4" somewhat uniformly, but no less than 4" in any spot. the perimeter is about 5" deep.
The pad is 12 x 26 ft with a bit of a triangular bump out because of the shape of the driveway and it just made sense.
the most weight it would ever have on it is a diesel superduty crewcab with a 10' camper - maybe 9000 lbs?here are some pics of the ground I am working on - the lighter colored patch is ridiculously hard - almost like concrete itself. In fact I used an electric jackhammer for the initial breaking up of the ground, and then an air chisel to get down to the right depth. I didn't want to go to deep with the jackhammer and disturb well compacted ground.
I have done some concrete in the past - poured a shop/garage floor in 3 pads of 11 x 12 ft, even excavated a basement in a house and poured concrete as well as some other projects. all of those were home mixed with a small electric mixer. this time around I am getting ready mix delivered (age catches up with us)

I am pretty sure that when I put in the shop floor, I put down some plastic first. that floor has been there for the better part of 12 years and hasn't cracked or anything. I think I did a pretty good job on it.
is this something I should do or does it matter?
compacting the ground? I really don't think it would do any good. I had a really hard time breaking this stuff apart and I have cleaned off most of the loose stuff. I don't see what compacting would do.
I understand that a concrete pro would do it 'right' but I have a 4" long arm lift that needs to go into a WJ and I want this pad done right now. I just need this thing done.
any thoughts, suggestions on the plastic and/or compacting or any other thoughts are welcome.

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It will be fine. No need for the plastic, that's to keep moisture from coming up through the concrete into a structure. I would recommend some wire mesh set on some 1.5" blocks or chairs to control temperature cracks. Do an expansion joint along where you have your triangle bump out to control expansion/contraction forces. Ground prep you have is fine. If you want to save some money on concrete, fill your low spots with class 7 or dirty base or whatever you have in your area.
 
Wet it down real good and pour it.

That is exactly what I wanted to hear.
On the finishing side of things, I've been watching youtube videos and some of the pros spend ages finishing - screeding, floating, mag floating, bull floating, edging, blah blah blah..
then just today I watched a video - screed, bull float, broom, done. I am pretty sure that is what I did on the shop floor but it was so long ago. I am definitely a function over form kind of guy so as long as it is solid, I am happy even if it isn't the prettiest.
I am definitely going with a broom finish - it is what I did in the shop floor and stuff rolls well and I haven't killed myself on spilled gear oil yet.
Man, I can't wait to have this concrete pad. should have done it ages ago.
 
I like rebar rather than the wire mesh, but that might just be the retardation in me
find a place that charges around 4 bucks a 20' stick of 3/8 and put enough in there that it looks okay
 
[486 said:
;n119489]I like rebar rather than the wire mesh, but that might just be the retardation in me
find a place that charges around 4 bucks a 20' stick of 3/8 and put enough in there that it looks okay

I prefer rebar also. If you aren't used to placing and tying rebar, it's miserable. The mesh is much easier for someone who rarely places concrete. Honestly for temp cracks, it works better too. Rebar is much better when you have forces other than compression going on and will work for temp so long as you have enough to traverse all the cracks you get.
 
With both wire and rebar make sure it's spaced off the ground with blocks and not just pulled up into the poor.
 
junkytj - are you thinking just one joint going straight across at the bump out? that would make a 12x12 pad against the shop and then a pretty big pad further out it would be 14 x about 14 (at the point of the triangle). I was thinking a joint where the bump out starts, and then another half way across that joint, going at 90 degrees so I would still have 3 good sized pads without any being too big or too small. I dunno, I've never had any of my concrete crack...... :grinpimp:

on the rebar - seems to me if I go that route it would be easiest to just lay them across each other and hit them with the arc welder? twist tying them all together seems like a real PITA. $4 a stick for rebar?!??! I guess I should have mentioned I am in Canuckistan - prob cost $40 a stick up here. the mesh is $24 bucks for 7.5' x 10' flat sheets. I used rolled once - never again. I would need .....5 sheets..... I guess. the concrete is 5.75 yards and costs $1160 CAD plus the taxes of about 12% . then the steaks and fixins for the helpers...... not cheap but long overdue.
 
I would throw in some expansion joints ( + pattern) plus rebar or mesh. Use 3k test or higher mud.

level the concrete off, bull float it, let it set up until it will take a broom. Then edge it and done. Set a couple of grade stakes in the middle to use as a guide when leveling it off. A couple guys and a 2x4 is all you need.


buy extra mud ( ~10%) and have a place to dump it if you don’t need it. Coming up short sucks :homer:
 
Not a concrete guy by any means but wire mesh and have them add fiber into the mix and send it? Thats the way me and the neighbor did a patch in our driveway a few years back and it has held up great
 
junkytj - are you thinking just one joint going straight across at the bump out? that would make a 12x12 pad against the shop and then a pretty big pad further out it would be 14 x about 14 (at the point of the triangle). I was thinking a joint where the bump out starts, and then another half way across that joint, going at 90 degrees so I would still have 3 good sized pads without any being too big or too small. I dunno, I've never had any of my concrete crack...... :grinpimp:

on the rebar - seems to me if I go that route it would be easiest to just lay them across each other and hit them with the arc welder? twist tying them all together seems like a real PITA. $4 a stick for rebar?!??! I guess I should have mentioned I am in Canuckistan - prob cost $40 a stick up here. the mesh is $24 bucks for 7.5' x 10' flat sheets. I used rolled once - never again. I would need .....5 sheets..... I guess. the concrete is 5.75 yards and costs $1160 CAD plus the taxes of about 12% . then the steaks and fixins for the helpers...... not cheap but long overdue.

It's going to crack at about 10' at 4" thick. Try to keep all dimensions less than that. That's not hard and fast, if you can make it with 12' sections, it will likely still work.
 
on the rebar - seems to me if I go that route it would be easiest to just lay them across each other and hit them with the arc welder? twist tying them all together seems like a real PITA. $4 a stick for rebar?!??! I guess I should have mentioned I am in Canuckistan - prob cost $40 a stick up here..

I've welded my rebar together before and well, once it is in place that's how it is
Kinda fucked up making a 5' cube of a cage that had to fit into forms. Sometimes tie wire is very much preferable to welding lol

canadiastan above mn? come on down to winnick supply in forest lake, bring your welding tanks to trade them in at the same time as they're also the cheapest I've found on that too
 
I think using rebar would be smart.. and I really think welding at the intersections would be a waste of effort, when you can just use those twisty pieces of metal.. of course long ago, on a site, I cut my hand pretty good trying to twist those thingys without gloves.. if you really want to there are all kinds of little things you snap on the rebar pieces, to hold them up in the air..

what does it matter if it cracks, anyways??
 
junkytj - are you thinking just one joint going straight across at the bump out? that would make a 12x12 pad against the shop and then a pretty big pad further out it would be 14 x about 14 (at the point of the triangle). I was thinking a joint where the bump out starts, and then another half way across that joint, going at 90 degrees so I would still have 3 good sized pads without any being too big or too small. I dunno, I've never had any of my concrete crack...... :grinpimp:

on the rebar - seems to me if I go that route it would be easiest to just lay them across each other and hit them with the arc welder? twist tying them all together seems like a real PITA. $4 a stick for rebar?!??! I guess I should have mentioned I am in Canuckistan - prob cost $40 a stick up here. the mesh is $24 bucks for 7.5' x 10' flat sheets. I used rolled once - never again. I would need .....5 sheets..... I guess. the concrete is 5.75 yards and costs $1160 CAD plus the taxes of about 12% . then the steaks and fixins for the helpers...... not cheap but long overdue.



Most rebar is not "weldable" sure you can weld it but it makes it incredibly weak. The purpose of the rebate may is to allow the concrete to flex a little without cracking. If you weld it it will snap at the welds.

Take a cheapo #4 bar or whatever you have and run a weld on it. Let it cool and then co wack it against a tree, curb, wall... and it will snap, amazingly easy.
 
share your wisdom/experience

I am tired of rolling around in the dirt to work on my junk, my friend's junk and my daughter's junk so it is time for a concrete driveway.
I have excavated 4" somewhat uniformly, but no less than 4" in any spot. the perimeter is about 5" deep.

Pics of your daughter's junk?







:flipoff2:

:lmao:
 
My uncle's 4" unreinforced driveway lasted 40+yr with an oil truck coming several times a winter. Honestly it was in pretty nice shape and easily had another few decades left when he tour it out and re-poured but he was also making the driveway much bigger at the same time.
 
3500# mix unreinforced, you'll be fine. As mentioned above, cut or tool joints in at about 10'.

I've installed miles of Vermont State Spec sidewalk. It's 5" unreinforced 3500# mix. Never once had an issue. Always installed on 12" of compacted 1.5" gravel.

Edit: don't install it dead flat. Make sure it has a 2% pitch to it to drain water. If you're going to salt it in the winter, seal it with a salt resistant sealer. Salt and concrete aren't friends.
 
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Wire mesh is useless, use fibers instead or nothing at all.

Rebar isn't needed for a slab on grade with a solid base under it. With only 4" of concrete, you wouldn't have enough coverage over the rebar anyways. Don't fall into the "it's concrete it has to have rebar in it trap"

Control joints are the most important part. Keep the panels as square as possible and with 4" thick I would shoot for 6' or less between joints. I prefer sawcut joints, but if you don't have a saw tooled joints work too.

Go with a 4000 PSI mix or even 4500 and pour it well and it will last forever.
 
Well it's happening this week - 5.75 yds of 4600psi concrete coming on Thursday. I went with the 10 Ga mesh, 6x6" in 10 x 7.5 sheets. Had a go at twist tying the sheets together last night and that sucked so I am just going to zap them together with the arc welder tonight, and hold them off the ground using chunks of broken concrete pads about 2" thick. Worst part will be the truck only has access from the short end of the pad so will have to wheelbarrow about 1/2 the concrete in place. Going to screed it off, do some amateur bull floating, cut in some control lines and edging, drag a broom across and call it good.
 
You will be golden. I missed the fiber recommendations. The fiber will work fine for concrete you aren't concerned about the finish on. Just in case someone runs across this later, until it wears off, be aware some of the fiber will be proud of the concrete like little fiberglass hairs. For interior or concrete where you may be laying on it, that's a miserable SOB. I've seen guys running razor blades on the end of scrapers to get rid of them. They will wear off naturally over time, but sucks until gone.
 
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You will be golden. I missed all the mesh recommendations. The mesh will work fine for concrete you aren't concerned about the finish on. Just in case someone runs across this later, until it wears off, be aware some of the mesh will be proud of the concrete like little fiberglass hairs. For interior or concrete where you may be laying on it, that's a miserable SOB. I've seen guys running razor blades on the end of scrapers to get rid of them. They will wear off naturally over time, but sucks until gone.

Wat?

I'm pretty sure "10 Ga mesh, 6x6" in 10 x 7.5 sheets." means

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You meant fiber?
 
We use "micro fiber" mostly. The days of "angel hair" fiber pretty much gone.
 
Well it's happening this week - 5.75 yds of 4600psi concrete coming on Thursday. I went with the 10 Ga mesh, 6x6" in 10 x 7.5 sheets. Had a go at twist tying the sheets together last night and that sucked so I am just going to zap them together with the arc welder tonight, and hold them off the ground using chunks of broken concrete pads about 2" thick. Worst part will be the truck only has access from the short end of the pad so will have to wheelbarrow about 1/2 the concrete in place. Going to screed it off, do some amateur bull floating, cut in some control lines and edging, drag a broom across and call it good.

make sure you get some of that "super plastisizer" (they might call it "water reducer" too) put in there, then you can get it flowing real good without it ending up with the strength of a dried turd

they should be able to throw it out to the far end reasonably well with that added in there, they'll toss a little at the near end to hold the mesh in place, then dump the rest real fast to get it to flow out as far as possible
 
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Aaaaaaand done! Turned out really well, best concrete I have ever placed. The driver was really good too, he helped out some - he had a great sense of humor and went well above and beyond what he was there for. As soon as I get a spare minute I'm going to call the company and see if they can recommend a meaningful gift for him...he looks like the kind of guy that would like some whiskey but you never know. We did it last Thursday and been keeping it good and wet. Should be good to go by the time tire change over has to happen
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