I had 18 yards of a driveway poured yesterday. Two 9 yd trucks. 1st truck came at 11, 2nd tuck just before noon. 85°, not too humid, beautiful weather for here.
The ground we poured on is undisturbed, harder than rocks after being driven on for a year. The very top is dusty, clay-like stuff that turns to elephant snot when it gets wet.
Around here, drives are usually poured on the ground, 3000 psi, no wire, no plastic, no fiber reinforcement, no cracks.
Finishers ran control joints across the 10′ drive about every 10′.
When I got there this morning, everything from the 2nd truck has cracks running the length of the drive, except one place where an inside curve starts, and probably should have had a control joint, but I’ve seen plenty with the same situation that didn’t crack.
5 gal of water were added to each load.
Concrete company says the ground was too dry, sucked the water out… should have run plastic, or wet the drive.
7 other drives have been poured in this subdivision at all times of the year, no special prep, no plastic, no fiber, no wire, no cracks. As a matter of fact, I’ve never seen plastic used in a drive, and wire and fiber only when there’s fill or sketchy dirt
Finishers say they got no idea. Never seen this.
The control joints were not especially deep, maybe 3/4″… the other drives have a bit deeper ones. Finishers used a window pane tool with joint groover on the bottom, so I assumed it was deep enough…, but I had them cut the rest of the joints on the good panes deeper today.
Tomorrow finishers will cut through the slab where good meets bad. They don’t have a way to get the slabs out, so Mon I’ll get my excavator to dig them up and haul them off.
Concrete company could do a core test on the cracked slabs but it’ll take 28 days, and might cost 2000 bucks. If it’s wrong they’ll eat it.
They’ll also give me the 4 yds we’re ripping out, for good will.
What I’d like to know is:
has anybody seen this phenomenon, is it even a phenomenom?
How would you deal with this responsibility-wise and money-wise?
If dogs run free, then what must be, Must be, and that is all. True love can make a blade of grass Stand up straight and tall. In harmony with the cosmic sea, True love needs no company, It can cure the soul, it can make it whole, If dogs run free.
Replies
>> Concrete company says the ground was too dry, sucked the water out... should have run plastic, or wet the drive. <<
and
>> They'll also give me the 4 yds we're ripping out, for good will. <<
Why didn't the first truck load crack???? Translation: concrete company doesn't want to admit they sent out a bad product.
I think you know I'm right down the street (more or less) from you. We had rain this past weekend. The ground wasn't that dry.... Besides - I had 28 yards placed last Tuesday. No cracks. Ground was fairly dry... Other specs were EXACTLY what you listed above. 3000psi blablabla... Only thing missing is what was the slump to start with? Any admixtures?
I'd be curious to see what the cracks look like. Plastic shrinkage cracks or something bigger?
PS: send me an E-mail with the concrete supplier's name. If it's the one I'm thinking of (very big around here) I can tell you some stories...
Edited 6/19/2008 8:12 pm ET by Matt
It's Pugh out of Silk Hope. Little company, I've gotten great service from them before. Won't use Chandler because of Mrs Snort's political reasonings<G>Not sure what you mean by plastic cracks. These run down the length of the slabs. They're not big, yet, but the one at the end of the pour goes all the way thru. These look like they'll only get worse.Supplied said the cracks looked like they be might where the excavator's bucket teeth are deeper than where the bucket scraped?Pics aren't too hot, I'll try to get some better in the am. Sorry dial-uppers, don't any one can see the cracks if I shrink them any further. If dogs run free, then what must be,
Must be, and that is all.
True love can make a blade of grass
Stand up straight and tall.
In harmony with the cosmic sea,
True love needs no company,
It can cure the soul, it can make it whole,
If dogs run free.
WOW dropping a quarter and it cracked!?
Musta been a heavy quarter. Don't do that again.Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
"We strive for conversion,we get lost in conversation, and wallow in consternation. "Me.
I don't know either of those suppliers you mentioned. We use the big guys because of the prices plus they can keep it coming as quick as we want it. Ordering 20 minute truck spacing is about average. The order backs is what can kill you though. I'll go out on a limb and say big companies have quicker order-backs. I hate cold joints....
Not sure about order backs? Is that getting more than you called for? Most companies here are pretty obliging, if, when you set up the will call you give them a hint you might need more... course it ain't an emergency til it happens If dogs run free, then what must be,
Must be, and that is all.
True love can make a blade of grass
Stand up straight and tall.
In harmony with the cosmic sea,
True love needs no company,
It can cure the soul, it can make it whole,
If dogs run free.
"order back" = I think we are just talkin' a mater of semantics... maybe you call it a "will call".
Full explanation for other readers here:
For last weeks pour it was a "20+" with 20 minute spacing. That is the way I ordered it: "twenty plus" (cubic yards). I estimated the amount of concrete required to be 27.5 yards. I ordered 20+, knowing that we would need a third truck. The "+" tells the batch plant a third truck will be required, but at the time of the initial order the quantity in the 3rd truck is unspecified. Once the first 20 yards were placed we estimated (actually "he" the concrete finisher) how much more was needed. We "ordered back" 8 more yards. Then the clock starts ticking. The last truck was there in about 30 minutes from the "order back" so there was no "cold joint". When all the concrete was placed the truck was "rattling" or nearly empty - so the amount of concrete purchased was close to exactly what was used. At ~$110+ a yard it's important. This is one reason for using large concrete suppliers - they have batch plants at various locations around the city - so they are never too far away - and they probably have at least a hundred trucks - so hopefully there is one ready to go when you need it.
This time we came out pretty close on the estimate as it wasn't a large pour. When doing house slabs or maybe a large driveway that might be say "40+" it can vary by a few yards. When doing several houses simultaneously or a very large footers it could vary by up to 5 yards - or maybe $600. I can get a pretty good dinner out for $600... :-) Estimating straight 4" flatwork you can get pretty close, but other things can vary - being 1/2 yard short doesn't cut it. My driveway has 49 yards in it - that's more than a few week's pay... :-)
Basically the way we get it. Will call has to do with the delivery time. I call the day before (or more, if I get a heads up from the finisher, or even hear a rumour of a busy day) and set up a will call for 18 yds + (we've got smaller trucks over this way<G>) 30 min spacing at 11:00.We usually do the will call because of weather, so finisher watches Greg Fischel, calls me at 7:15, I call for the crete, or cancel.So back to my original curse, the plot thickens... or thins? I misread the water added on the first ticket. It was 50gal instead of 5.0! The second load that cracked was 12 gal.Gonna tear up almost 8 yds Mon. Concrete company will only replace 4. I don't see it as the finishers fault, so I'm paying them extra for the re-pour.It will be interesting to see what we tear up. Pugh thinks it's powdery dirt in the skidsteer tooth tracks. Okaaaay.I'll put down plastic, jeeze, order fiber (which instead of the everyday low price of $5yd, the owner will throw in), and might have a drive by Tues evening.Hey, good thing though, I'm only paying $102/yd and it's supposed to rain this weekend... got made or what? LOL If dogs run free, then what must be,
Must be, and that is all.
True love can make a blade of grass
Stand up straight and tall.
In harmony with the cosmic sea,
True love needs no company,
It can cure the soul, it can make it whole,
If dogs run free.
i been reading but staying out, the crack is a stress crack from curing too quick, too much sun on that load. settlement crack wont happen for months, so it not structual, just ugly. Concrete psi wont happen for at least a week.really the concrete company off the hook at this point. this was contractor error. Its also why we place at night.
So, will the plastic help for the next pour? Tuesday looks like 87° and partly cloudy... gotta get it in. No residential nothing goes on a night here.I'm the gc, looks like I'm eating a concrete sammich. If dogs run free, then what must be,
Must be, and that is all.
True love can make a blade of grass
Stand up straight and tall.
In harmony with the cosmic sea,
True love needs no company,
It can cure the soul, it can make it whole,
If dogs run free.
Do you think they'll get worse? The stress cracks running down the drive?The section with the corner crack has gotta go.Should I call for a retarder in the mix?Concrete is not my friend. If dogs run free, then what must be,
Must be, and that is all.
True love can make a blade of grass
Stand up straight and tall.
In harmony with the cosmic sea,
True love needs no company,
It can cure the soul, it can make it whole,
If dogs run free.
I beleiev in the three plastic, plastic vapor barrier, super plasticer, and plastic fibers. I use all three on every placement. and also place about 6 am and once you get done, very very important. hose it down and cover with plastic for seven days. uh, dont want hear it, just do itno more than 2 gallon per yard, cant get it right send it back
Edited 6/21/2008 10:45 am by brownbagg
Thanks, I'm saving that... how's plastic do on a window paned broom finish? If dogs run free, then what must be,
Must be, and that is all.
True love can make a blade of grass
Stand up straight and tall.
In harmony with the cosmic sea,
True love needs no company,
It can cure the soul, it can make it whole,
If dogs run free.
let it set up first, coouple hours then cover
Damn, this is getting expensive! If dogs run free, then what must be,
Must be, and that is all.
True love can make a blade of grass
Stand up straight and tall.
In harmony with the cosmic sea,
True love needs no company,
It can cure the soul, it can make it whole,
If dogs run free.
In that pour I was talking about last week I got retarder on recommendation of the concrete company. It was 98º that day. They recommended 3 oz of retarder per yard and chilled water. I got 2 oz per yard as the finisher wasn't too crazy about the idea. I didn't get the chilled water. It still seemed to be too slow. The person at the batch plant said 1 oz would buy you 15 minutes. It was broomed and picture framed. I think the finishers got tired of waiting for it. It came out OK, but the broom finish was a little rougher than I really wanted. The first truck rolled up at 7:00 AM and the finishers left at around 11:30.
Gotta admit - your scenario sounds like a nightmare.
It's really hard for me to believe they put 50 gallons of extra water in one truck. The amount of water added really depends on what slump is ordered and what actually arrives at the jobsite. Sometimes you ask for a 4" slump and it won't even flow down the cute. 50 sounds crazy though...
BTW - I'm no concrete finisher but I watch what is going on closely when I'm paying - which I always am. I got in a pi$$ing match with a turn-key concrete company last year. They had the concrete supplier tell me that adding 20 gallons was fine and they did it every day. Funny how that turn-key companies stuff tended to crack more often (although I never really had any catastrophic failures like yours). I don't use them any more though. Maybe it's none of my business but another thing that also pi$$ed me off was that they paid their guys the absolute minimum and charged me the max....
Yeah 50 gal does sound a little much, I've got to check that out. But if it's right, I'd better do the same with the next pour, right, it worked <G>Not really a nightmare, just a danged expensive lesson... it's a spec :-(It might really be that the powdered dirt in the skidsteer tooth grooves are where the stress cracks are. I'm a fugging concrete detective. I'm thinking I'm eating the whole tear-out/ replacement now... next custom's on the drawing board... no place to bury the sheeit<G>Hey, email me your phone number, I had to go to Cosmos Granite and then Custom Brick last week, was gonna call, but couldn't find your number... gawd did I get lost, don't know how you do it<G> Now you see this one-eyed midget
Shouting the word "NOW"
And you say, "For what reason?"
And he says, "How?"
And you say, "What does this mean?"
And he screams back, "You're a cow
Give me some milk
Or else go home"
Just so you won't feel alone on the "bad trip" I got 2 houses framed right now with problems with the steps... Bad plans.... actually one I could use some experienced advice on...
If it was easy, even a caveman could do it...
My current building site is 3 miles from Custom Brick.
Phone # is in your E-mail
Good maybe we can cry in our beers over a 3 martini lunch<G>I love it when the stairs are just stuck in the plans and the architect says "oh, just do your carpenter magic thing" as he waves his hands and acts like he's pulling a rabbit out of a hat. That's when I say " oh, you wanted them to go up?" Now you see this one-eyed midget
Shouting the word "NOW"
And you say, "For what reason?"
And he says, "How?"
And you say, "What does this mean?"
And he screams back, "You're a cow
Give me some milk
Or else go home"
Here's the quote:
"subject to field adjustment" :-) Or how about this one: "Just fake 'em in there".
Me and DW went to Hillsborough Hog Day today... Is that near you?
I'm down south in White Cross, just off 54. Did you see the Fawcett bros silver Pontiac collection at Hog Day? I missed it, was watering the little crete I have left... til it rained<g> Now you see this one-eyed midget
Shouting the word "NOW"
And you say, "For what reason?"
And he says, "How?"
And you say, "What does this mean?"
And he screams back, "You're a cow
Give me some milk
Or else go home"
I did look at the cars including the Pontiacs. I saw several other late 60s early 70s "muscle cars" that brought back memories of high school. Back then only "rich kids" had cars, especially those kinds. Remined me that back in the mid 70s I briefly owned a 57 Chevy Belair but just didn't have the resources or the place to keep it.
BTW - I don't drink before 5:00 PM on work days. One of my first jobs I worked (briefly) with a guy who drank during the day and I promised myself that that was one line I'd never cross.
Not even one little martini??? I am kidding, but...Worked for a guy whose super would start cracking buds around 11 every morning, and keep cracking them 'til 8 or 9 at night. Worked his butt off the whole time, cleaning jobsites, calling clients, ordering, coordinating. Couldn't drink at home, so he'd just stay at work...quit drinking and now is the laziest, slackest, lyingest super we work for. Now you see this one-eyed midget
Shouting the word "NOW"
And you say, "For what reason?"
And he says, "How?"
And you say, "What does this mean?"
And he screams back, "You're a cow
Give me some milk
Or else go home"
Back to your issue, here is what I think now (now that the 50 gal thing came out and I had some time to think about it):
Concrete supplier is right. Substrate was too dry. I've never had that happen, but that's why I'm here - to learn something other than via the hard way. I think I've seen soil like you describe around here but never had to put concrete on it. Was the dust white? The reason the first truck load didn't crack was because it was so watered down that the substrate couldn't possibly suck all that water out of it. I really think you need a new finisher - simply by virtue of him adding 50 gallons to a truck load. That, and if the substrate was so dry as to cause this problem, he should have known it - as a concrete professional. I think he needs to remove the bad concrete for free too. If you have him remove it, I guess you are compelled to use him to finish the job. I'd talk to him about the 50 gallons. Then tell him he is gonna remove the bad for free. Even if you have to pay for removal from site and dump fees it should only be about $300. The jacking out is gonna be the big expense - as you probably know, jacking it out is generally 2x the labor charge of placing it. For turn key subs they generally charge the same thing to remove as they do to install (L&M). I'm not so sure he should be paid 2x for placing it either. One of my co-workers has a sign in his construction trailer: "I only pay for concrete once!". He uses turn-key concrete guys though - so in that scenario it's all on the sub - when you are supplying the concrete, that puts some responsibility on you.
If your finisher refuses to accept any responsibility, and you don't have another immediately available, I have one but I'd need to talk to you on the phone about it. He isn't the sharpest knife in the drawer... but he does OK. I'm not positive he'd go that far though... but he probably would.
You're right, these are not the best finishers. I've seen some of their work, and they're not worst, either. I do have another, actually a couple, so, if push comes to shove, these guys will go.Powder isn't white, it's tan, same as the dirt, harder than hell, til it's broken up, or wet.Supposed to be a lot hotter this week, I'm going with Brownbagg's suggestions.Gotta get it out and in, sort it out later. Now you see this one-eyed midget
Shouting the word "NOW"
And you say, "For what reason?"
And he says, "How?"
And you say, "What does this mean?"
And he screams back, "You're a cow
Give me some milk
Or else go home"
Heres a story for ya. I was supering a set of framing crews, same designer, bunch of different designs. Kept having trouble with his head room on stairs plus some other issues. Finally after listening to him blame the carps for everything I told him to meet us at one of the houses job with the developers super.
Did a quick walk though, hustling from room to room, on the excuse I had an appointment I needed to be to. Pointed out his design issues versus reality in a few places in the house then headed down the stairs two at a time.
He was almost running to keep up when he hit the low headroom with his forehead. I ducked he didn't. I turned around and said:
" Oh yea, we have a problem with the stair head room here, I almost forgot. Developers super damn near shid himself laffing.
They can't get your Goat if you don't tell them where it is hidden.
That's good, and I'm stealing it.Had one set where going down you'd have to duck, coming up you somehow missed it. Had to get the inspector into the basement first for the co... luckily the HO's were height challenged. Now you see this one-eyed midget
Shouting the word "NOW"
And you say, "For what reason?"
And he says, "How?"
And you say, "What does this mean?"
And he screams back, "You're a cow
Give me some milk
Or else go home"
Pretty funny... Better still I bet that guy will pay more attention to the size of stair holes...
One of my houses had a head height problem. I had them fix it with a sawsall. Not pretty and I feel an engineers letter comming on.
I beleiev in the three plastic, plastic vapor barrier, super plasticer, and plastic fibers. I use all three on every placement.
Brownbagg,
I've only used super plasticizer once, for the floor of 16-ft. x 12-ft. storage building. Placing, screeding and floating the concrete was as easy as it gets. It seemed to "go off" real suddenly, though, and I had to scramble to get a smooth finish. Is this normal for plasticized concrete? And do you use it for large floors that have to have a slick finish? BTW, thanks for all the concrete advice on this forum.
yes, you have about 45 minutes once it down
50 gallons!!!??? That can't be right.
That's what I thought, too... must be really good water, it's the best part of the pour, so far! If dogs run free, then what must be,
Must be, and that is all.
True love can make a blade of grass
Stand up straight and tall.
In harmony with the cosmic sea,
True love needs no company,
It can cure the soul, it can make it whole,
If dogs run free.
Brownie might disagree with me but I would guess it was because of what we call a "hot" load.
Truck wasn't completely emptied from previous pour and the batch plant topped it off and sent it to you or the truck had been to another job and got rerouted to you after it wasn't needed there.
Have your batch tickets? check the times and weights , might tell you something.
One ticket says 9:55 other says 10:31. Plant is about 1/2 hr away.My thoughts are the crete, too... any way a "hot" load would show up in a test?The garage panels are fine.The last three, and part of another are the crackers If dogs run free, then what must be,
Must be, and that is all.
True love can make a blade of grass
Stand up straight and tall.
In harmony with the cosmic sea,
True love needs no company,
It can cure the soul, it can make it whole,
If dogs run free.
Not really that I know of. At least not easily, maybe possible if tthey can look for additives, I am not knowledgeable enough to say. Testing usually tests for compressive strengths over a given period of time and matches it against what the mix design was.
Shout out to Brownie and can probably tell you. The cracks look like shrinkage though.
Other thoughts are was the area the cracks are in in direct sun before the pour? Heated subgrade can cause the mud to go off early and fast, as can direct sun on one part of a new pour and shade on another part.
Was a "cure" spray applied onto the slab or wet blanket applied after the pour or anything that would slow down the water loss time?
Did the wind come up after the first truck ? Lots of possibilities.
They can't get your Goat if you don't tell them where it is hidden.
there's at least a couple of us wondering what your take on this cracking crete prob is. care to share an opinion?
Pour is on the east side, shaded in the early morning, late morning sun, afternoon shade.Zephyrs of wind...but I've seen pours in the worst of conditions hold up, and I've had extra concrete dumped where I wanted it to crack, why doesn't that ever work out?<G> If dogs run free, then what must be,
Must be, and that is all.
True love can make a blade of grass
Stand up straight and tall.
In harmony with the cosmic sea,
True love needs no company,
It can cure the soul, it can make it whole,
If dogs run free.
So, the first truck backed in to the drive and the load was placed and the truck pulled out. The second truck also backed into the drive over the same track as the first and pulled out.
The supposely hardpacked substrate was disturbed by two heavily laden trucks and the result was a pair of long impressions with a ridge or two of earth forced up.
Was the depth within the forms rechecked before starting or during the pour? Perhaps you have a radical change in pour thickness in the vicinity of those long cracks.
Would those cracks happen to coincide with the wheel base of the trucks?
Ralph, actually the first truck couldn't quite make the turn enough to get the chute close to the garage... there was some back and forthing along with some heavy wheel cutting... hmmmm.But the dirt is extraordinarily hard, and packed... finishers couldn't gnaw down the 4" we needed to go with their little bobcat, had to get a big, tracked JD skidsteer in... and the dry stuff on top is like talcum powder, so I don't think there were any tracks to speak of... will check that out in the morning... If dogs run free, then what must be,
Must be, and that is all.
True love can make a blade of grass
Stand up straight and tall.
In harmony with the cosmic sea,
True love needs no company,
It can cure the soul, it can make it whole,
If dogs run free.
Was this ceement covered with plastic to protect it from the sun and/or drying too quickly?
Any curing compounds?
Nope, no plastic, or compounds other than elbow grease.
If dogs run free, then what must be,
Must be, and that is all.
True love can make a blade of grass
Stand up straight and tall.
In harmony with the cosmic sea,
True love needs no company,
It can cure the soul, it can make it whole,
If dogs run free.
Hey Brownie, where you at? If dogs run free, then what must be,
Must be, and that is all.
True love can make a blade of grass
Stand up straight and tall.
In harmony with the cosmic sea,
True love needs no company,
It can cure the soul, it can make it whole,
If dogs run free.
That's exactly what I was thinking. If I had a batch of concrete that someone else didn't use I'd be mighty tempted to re-use it.
Once you mix concrete up you can't just mix it forever and still have it work.
I think it becomes wet not hard concrete that has already done it's thing. It's gone.
I learned that from mixing mortar to much and to long. Throw it out and start over.
Edited 6/19/2008 10:08 pm ET by popawheelie
The setting (hydration) of Portland cement based products like concrete and mortar is a chemical reaction so adding more water is not going to stop it from getting hard. There are accelerators and retarders that can be added to vary the set time though.
About a year ago I had a concrete truck break an axle (actually 2 axles) in the driveway of the pour. The full truck was immobile. They added some kind of chemicals to the load to slow the hydration and 2 mechanics were on site in less than an hour changing the axles on the truck which was blocking the road. They had a heck of a time getting the broken axles out and they definitely had out every "big hammer" they had on their truck.
The concrete company's supervisor and supervisor's supervisor were on site at 6PM with grim looks on their faces. They told me that if they didn't get the truck fixed pronto the drum (10 yard truck) would have to be removed and thrown away.
I personally felt the concrete sub was responsible - for leaving a pile of gravel in the driveway that the truck had to back over. I had asked them to move it the day before (it was their gravel) and got one of these "don't worry about it" we will take care of it type of answers. What happened was that as the truck tried to back up it started getting stuck in the gravel. Then when he went to pull forward, the wheels were spinning and then the truck moved forward. When the spinning wheels hit the concrete valley curb and grabbed traction and there was a bang and that was all she wrote. Not a loud bang - more of a thud - but when you got a truck weighing 50k#s (or whatever) thick steel can break in a heartbeat. I'm sure that the (apparently new) driver learned a thing or 2 also - even if he no longer had a job... Mean time my house slab ended up with a cold joint in it.
I have heard of in similar situations adding 50 pounds of sugar to the drum, supposed to retard curing.
Several weeks ago a cement truck driver told me that there were chemicals availble to stop the cure process and then complimentary chemicals to start it back up. Not sure if he was pulling my leg or not.
The second batch was bad. The concrete supplier owes you removal and disposal of bad batch ,new concrete and labor. In other words,if they do not agree ,get a lawyer.
I have seen something similar years ago. The supplier sent out a rep to look at the slab. We were fully reimbursed without any problems. In this particular case the water metering system went on the blink.The resulting mix never came up to 2500psi.
mike
The owner is acting like he wants to be a stand-up guy, and he has always seemed like a straight shooter in previous dealings. He came out to look at the slab and came up with the too dry soil, bucket teeth things.When I asked him why the first load didn't crack, he said I was just lucky... I'm not exactly feeling that way :-( If dogs run free, then what must be,
Must be, and that is all.
True love can make a blade of grass
Stand up straight and tall.
In harmony with the cosmic sea,
True love needs no company,
It can cure the soul, it can make it whole,
If dogs run free.
All concrete will crack somewhere at some time. Control joints are installed to try and control where it will crack. What you have does look like shrinkage cracks, which is often caused by moisture being pulled out of the concrete too quickly, before the cementitious materials have a chance to hydrate to their initial set point. The one picture of the crack running parallel to and right near the edge of the "picture frame" is a good example - the edge most likely "dried" too quickly.
BUT ... all the ideas that have been thrown out are also possible. I will also throw out two more - the temperature of the concrete itself could have been a factor. In commercial construction we reject any concrete with a temperature above 90*. With an air temp of 85*, the heat of hydration released by the concrete could have easily raised the temp in the drum to well over 90*. We also use a 90 minute rule for placement. Concrete has to be placed within 90 min of being batched. You said the 2nd truck was batched at 10:31am and that he arrived shortly before noon. That is pretty close to the 90 min window. The time combined with temperature could have been a factor.
But all in all concrete is a wicked mistress - we try to control it as best we can - but it will often do what it feels like despite our best efforts.
Shawn
Shawn
-------------------------------------------------------------------------------
Checker Contracting - SE Michigan
That's very interesting... So that I understand this more completely, let me ask you this: Let's say that the outside air temp is 95º - do you still reject loads that have a temp of 90º or does the reject temp vary by air temp. I guess the idea is to gauge if the hydration process has started yet?
I like that 90 minute rule too...
Edited 6/20/2008 7:50 pm ET by Matt
Do not allow any water to be added at the jobsite.
Jeff
"Do not allow any water to be added at the jobsite. "
Sometimes it just plain won't slide down the cute.
So, what's the end of the story...
S'not over... had the cracked stuff removed, rained the night before the next pour, put down plastic, got fiber, finishers called as they were brooming... cracked again... more to come, dang it<G> Now you see this one-eyed midget
Shouting the word "NOW"
And you say, "For what reason?"
And he says, "How?"
And you say, "What does this mean?"
And he screams back, "You're a cow
Give me some milk
Or else go home"
I think you are right - concrete is not your friend....
Cracked in the same configuration as before?
No significant thickness differences in the pour in that area? As in: you did rescreed and evenly compact the substrate? The guys I use will string across the forms and make sure the depth of the pour is very consistent.
Finishers didn't add water to the pour or baptize to make the float easier?
Different, first cracks ran lengthwise, across the brooming. This time more random, diagonally... and except for one, I think it was the expansion joint depth. Probably a good idea to string, but these were just sloppy finishers... my fault...And, no water added to any of the second pour's trucks... now, the very first truck, whose load had no cracks, had 50 gal added... concrete co. pinged it a week later and got 1800psi??? Now you see this one-eyed midget
Shouting the word "NOW"
And you say, "For what reason?"
And he says, "How?"
And you say, "What does this mean?"
And he screams back, "You're a cow
Give me some milk
Or else go home"
pinging is a joke, but 1800 is about right for 7 days. but the problem is not the concrete but the subgrade, forms and finishers. concrete if bad is not going to crack till a load is applied.
Well, then I have no doubt it will crack later...LOL! Now you see this one-eyed midget
Shouting the word "NOW"
And you say, "For what reason?"
And he says, "How?"
And you say, "What does this mean?"
And he screams back, "You're a cow
Give me some milk
Or else go home"
You may want to contact the folks at http://www.cement.org/