Will it be ok? This driveway is enormous, so there is no way of covering it. They probably finished pouring about 4-5 hours ago.
Best case scenario, you'll probably end up with the aggregate exposed, which is an upgrade finish to choose. That's if it is formed properly, with the right slope and crown to shed water and the mix was right. In the heat, crete sets up quick.
Worst case scenario is that it was a light mix on portland, the grading and forming was off, and you get rivers running over it, washing swales into it.
No driveway is too enormous to be covered with poly sheeting. You can get 100' rolls easily. And this Should have been done if pouring rain was in the forecast.
It should have been covered. Depends on how set the concrete was when the rain came, but in my experience spalling is a likely possibility, if not soon, probably after a season or so.
Are you in snow country? If so, the spalling will probably be even worse due to freeze/thaw cycles. If the surface is not materially affected as hollysprings describes, you may want to seal it to help with possible future spalling.
The rain will cause the concrete to take longer to cure, but don't take this as a bad thing! The longer concrete is allowed to cure the better the different compounds and components will bond together!
Poured a lot of concrete with an old timer who always used to say concrete best cures under water.
So as long as it was starting to set up for you (which after 4-5 hours very well should have) you should have no issues and may very well be benefiting from it.
It looks fine today. It was sealed and it was cured enough for them to cut the lines into it, which my husband things means it must have been set enough for it to withstand the rain ok. Might I still have issues?
Your description sounds as if everything is perfect. Once it is set enough to not wash anything away, more water helps concrete to cure stronger.
I'm no expert, but I thought concrete was supposed to be covered to keep moisture in, not keep it out.
We have some cracks already. Is this normal? What's the fix?
There are several reasons concrete can crack this fast, none of which are good.
Where are you and what is the weather like? Can we get a picture showing more, all of the driveway?
three3apples - ugh you have really had a go with your build. :( Our experience - same issue with concrete pour followed by rain and hard rain about 1-2 hours after trowel was completed. We didn't have gutters installed yet. Where the rain fell off the roof we had definite and immediate damage. A nice line of exposed aggregate on the walk to the garage door. Where the driveway itself got drenched so far it looks okay. The cement sub said to keep an eye on it and we'd know for sure after we have a winter (ugh) and he'd stand behind it and re-do if needed. They re-poured the walk way the very next day.
Our porch which was poured a different day and is covered has some hairline cracks that have grown some. Not happy with that as they are near a corner and we don't have the pillars installed yet. I think he'll be re-pouring that section too hopefully before winter so we can put the pillars up and be done with this thing!
We are in NE Ohio. I'll take a photo of as much as will fit in one view.
What might have caused this? I'm so irritated. What I read online suggests that it's normal for concrete to crack. This particular crack goes all the way through. Is that worse?
It was mid-80s yesterday and we had a thunderstorm at 8:30 pm. It's been hot all day today, no rain.
Here you go:
Concrete made from Portland cement shrinks slightly as it cures. Reinforcement is one way to keep a crack from being very big at any one point. Cutting of control joints is to create weak places at specific locations so that cracks will occur there and cracking will occur below the surface of the concrete.
Concrete generates considerable heat for several hours during the initial cure stages. Heat expands concrete. As it cools, it contracts, increasing the likelihood of cracks.
Most concrete has cracks or soon will have them.
Here is how it is today:
Is that the only crack?
I believe so, but I didn't walk the whole driveway today.
Looks like the crack follows the control joint on the surface. Exactly as expected. Even Congress cannot keep it from happening.
Find other things to fret about.
I, too, am curious if there are any more cracks. Do you have pictures of the formwork and reinforcing before the pour?
I totally disagree that this is nothing to worry about. Hair line cracks after the concrete has cured is one thing but ones that big days after the pour are not right.
I have seen many things that can cause this usually there is more than one spot. Check your whole slab.
Are the cuts made with a saw? Hard to tell from the pic. How deep are the control joints?
The control joints go all the way through it seems. I'll check the whole driveway this evening.
Yes, the cuts were made with a saw.
I heard my husband say something about a mesh going down under the concrete, but that's all I know.
Looks like we have cracks at about half the joints.
Did you check on how deep your control joints were? Cracking at them is good, they are doing there job. I just have never seen such heavy cracking so soon in a slab. I am very curious to know what reinforcing was used.
When was the dirtwork done for this pour? I don't see any real lawn disturbance at all adjacent to the drive, and you'd expect some. And it's hard to tell from thhe pic, but it doesn't appear to have a swale graded into it for water management. How much stone is under the crete? Did he compact properly? When did this alll occur?
We had the driveway compacted 11 months ago. There was quite a bit of stone under, at least four inches. We have mesh under the concrete instead of metal. We have no lawn within many feet away from the driveway. My husband seeded the lawn recently, but stayed away from the driveway.
The company owner called after seeing my photos and said the cracks on the joints are normal for a summer pour. The other two are going to be fixed early next week.
Fixed? What is he fixing?
I am NOT a fan of using mesh instead of rebar. It is not structural at all.
Still curious to the depth of the cuts.
From what I am hearing I am assuming the cuts are quite deep, the substrate wasn't moist before the pour and the concrete wasn't cured properly, especially for the size of the pour.. Thus you suffered extreme cracking from shrinkage, as stated by another poster, from heat of hydration and the ground wicking moisture out.
I am guessing again but I think the worst crack that isn't in the control joint is because the cuts are deep and they didn't run the saw out the sides. Thus the concrete is full depth at the edges then tapers down to the depth at the cut, probably around 12" in (assuming a typical 14" saw was used) The crack followed the control joint until the concrete started to get thicker and it found an easier path.
I don't like the comment that this happens in summer pours. How many driveways does he do in the frozen winter, my guess none. If my speculations are correct this only happens when concrete is poured on a dry substrate and improperly cured later. At a bare minimum he should have either had sprinklers running on the concrete having you move them around or the best would have had the slab covered in burlap and kept constantly wet. I like to keep the slab moist for 3-4 days in the hot summer. Even if it is just turning the sprinkler on a few times a day.
My husband decided to use mesh because it is more easily repairable. Neither of us have experience in this and he was advised this was a good option. It's a class C concrete, if that helps any.
Cuts are an inch deep.
Cuts are appropriate for the depth of the slab. But should have run out the edges.
The cheapest thing you can do for a slab is add more appropriately placed rebar. While mesh may suffice for you, I would never, ever, solely use it.
Methinks your slab will be "ok" in the end but it could have been better.
The thought of using mesh because it is easier to fix is not that sound...Place concrete properly to never have to redo it.
Other opinions may vary, but with cracks like that I would consider filling the construction joints with Sika flex. In your freeze thaw climate you don't want water penetrating through the cracks.
SGC, thanks for your helpful advice. Some of the cracks extend into the cut joints. Should we put that product in there, too?
My husband also said that since many of our neighbors' concrete driveways have rust stains that have shown up after a year or two he wanted to avoid the rebar under ours. We have fibers in our concrete, not sure if that's relevant at all.
Fibers do help control hairline cracks.
Rust stains in the neighbours driveways is cause from something else than properly placed rebar.
Yes, with cracks like that I would seal all cracks and construction joints. If there any more that are that size that you can fit a coin in, water is going to be an issue, or maybe not BUT you spend a pretty penny on that expansive driveway. Risk vs Reward. Protect your investment.
Hope all the best.
Concrete cracks. It's the nature of the beast.
Just wanted to update everyone. We had an engineer come out and test the hardness of the driveway. It was 2500 psi after 21 days, said it would continue to harden. The cracks are fine, the control joints not going all the way to the edges were due to laziness on the part of the guy doing the cuts, he said. All seems to be ok. The man in charge of the pouring has not yet been out to look at it, however.
Just as I told you on August 28.