We are about to try to pour a new church parking lot – approx 100×100. This is by far the most concrete (two of us) have ever attempted. (we have done driveways, basement floors, etc.
We are planning to pour it in 10 ft strips, nothing fancy, 4 inches thick, 1/2 rebar every 2 feet both ways, float and brush.
We have the idea that we will use a split 2 in PVC pipe on the inside of a form to make the next strip “key” in. Is this a good idea or not?
I have a good float with a “knuckle head”, and we will be able to get the concrete truck everywhere (no wheeling).
We will be able to have volunteer help for placing.
We have a good drainage spot for the extra water.
Does anybody have any pointers or counsel on this?
Tx
FZ
Replies
I would be hesitant with the 4-inch thickness, and the rebar spacing.
This depends on how good the base aggregates underneath it are, but you are were there are ice and snow. The water is going to get under the slab in the winter, and heave the slab along the joints. When it does, the load from the cars will crack it.
Also, the water that is under there will carry out the fines in the aggregate as it gets pushed out by the cars driving on it in the spring thaw. That results in a void, that will also tend to crack the slab from the load of the cars on it.
I think a 6-inch slab, on 6-inches of well compacted base, with #4 bars on 12-inch centers would be more appropriate.
Check with city/county public works as to what a commercial driveway requires, and that should hold up.
The church is probably cash strapped, and the added expense will be a problem, but the thin slab will be prone to problems in just a few years, and the thicker one should last for twenty plus years.
I just read all the posts - you mentioned the base. We have had a gravel parking lot for over 50 years. That's the base.I would like to key it all together with the rebar, and we have a way of doing that (with removable triangles under the bars) but I am afraid of the hazzard of leaving them stick out for any length of time considering kids, etc. Maybe you have a solution.Man, I don't think we can go 6. Is #4 rebar is what thickness? (guess I need to look it up). Has anybody used that funny looking triangle screed on a handle on ebay? Is it a joke? How much slope for drainage? Cure with plastic? yes/no, or spray? The consensus is the key idea isn't a good one? It wouldn't work or trap water and make it pop?We are going to have volunteer help when placing it. Then we will just float and brush, so I think we can struggle through it. It won't be easy. Our largest pour to date is 15 yards. This will be around 160 I think.
Edited 4/18/2008 1:26 am ET by Fonzie
Do yourself and everybody else a favor and do it in two or more pours or find experienced help.
10,000sq./ft. @ 4" deep comes out to 124yds. exact, unless the sub-base is perfect you will always need more so 140 or so is probably a good number. The agony of fighting that large a slab with inexperienced help is simply not worth it, would you rather go slower and be proud of what was done or be taking a jack hammer to what went wrong?. #4 bar is 1/2" , rebar is sized by number, each increase in number amounts to 1/8" (#3= 3/8", #5= 5/8" etc.) The 6 " thickness is to support the weight of the vehicles that will be on the slab and the abuse the slab will take over years to come.
They can't get your Goat if you don't tell them where it is hidden.
Are you and I the only two who think that doing this with two guys is nuts?? A pro crew on a slab this size would be a dozen guys. Two guys... what's that, one on the chute and one on the rake?
The OP has mentioned volunteer help but hasn't given a number of bodies only that the volunteers are inexperienced.. Yes I think it is nuts if only he and one other somewhat experienced guy try to do much of that area even with volunteer help. I would do a couple of garage sized areas a day, at least to start, then if the crew jells finish up with a large area as the grand finale. It sounds as if he is desperate to get it done for his church which I can understand.
But he hasn't yet lived the desperate of 10 yds of mud setting up, aging volunteers falling out like flies in a freeze and either an incoming rain storm or alternately a hot dry wind. Be hoping for his sake his church has the connections to the right God. He is going to need all the good help he can get.
Edited 4/19/2008 8:27 pm by dovetail97128
Dave he said he had vol. help. I hope he does this in seversl days, thats a lot of concrete to put down in one pour with vol. help.
OP's 1st. post did say he intended to pour in 10 wide strips. If he does that for all 100' it would be somewhere near 17-20 yds. a pour. Not too bad , but screeding that amount of linear ft. is going to be hard on somebody. IMO It is all going to depend on the quality and physical shape of the volunteers.
They can't get your Goat if you don't tell them where it is hidden.
Two guys? I would never attempt a 10K foot slab with that little manpower.
I'm with "Jigs-n-fixtures" in thinking that 4" might be a little thin.
Definitely make sure the base is well compacted.
I've never heard of anyone trying to "key" the concrete like you're thinking. Interesting idea, but I have no idea what would happen.
Boss, We have used this stuff or a product like it for years. OP is trying to do the same thing . Scroll down to plastic keyway. http://www.masco.net/catalogs2/concrete_forming_accessories/slab_horizontal/screeds.htm
They can't get your Goat if you don't tell them where it is hidden.
Thanks - I had never seen those things before. Concrete isn't something I'm an expert on by any means...
Just 2,953,377 more days till I start caring what you think.
I agree with others about the thickness and the rebar schedule.
As far as "keying", the rebar should satisfy that function, but you should be running some control joints. If you don't have one, you should borrow or rent a jointer that fits on your float handles.
IMO you would be better to pour larger square sections rather then 4' wide x 100' strips.
EDIT:(Splintie points out that this isn't what the OP was planning. he is planning 10' wide strips.. helps to read AND comprehend what is being posted before replying. )
5-10'x 10' sections at a time is slightly more sq ft. and close to the size of a 2 car garage for comparison.
Doing a 10' by 50' strip that is then "soft cut" into 10' x 10' squares would be better yet and will reduce the odds of unwanted cracking .
6" thick , 1/2" bar 24" o.c. Any parking area for a church is going to have some heavy loads on it at some point in time .
You don't need the "keyway" if you are using the bar to lock the slabs together, but if you choose to use it there are commercial available products for this. (see my post to Bosshog above)
Edited 4/17/2008 6:02 pm by dovetail97128
From OP: "We are planning to pour it in 10 ft strips"(No, as a matter of fact, i DON'T have anything better to do today! <G>)
DUH. Well proof reading has always been an honorable ( if sometimes sneered at ) profession. And I shouldn't answer posts without at least 2 cups of coffee in me to wake me up.
They can't get your Goat if you don't tell them where it is hidden.
We're both having drug troubles today: i've had just enough Lortab to make me cross-eyed and you're suffering a dearth of caffeine. I'm thinking of going outside and seeing if i can hurt myself putting Tanglefoot on the fruit trees...
Lack of caffeine and a bout with a late flu that has hit town. Has me mostly couch bound last few days.
They can't get your Goat if you don't tell them where it is hidden.
I'll take 'hurt' over 'sick' any day. I probably should stop posting to you so that i don't get infected with whatever you've got.
A few months ago I was reading a pamphlet on pouring slabs published by one of the concrete organizations (don't remember which one). They recommended that poured sections should be square or nearly so. IIRC, they suggested 15' square. I thus agree with the above post stating that the pour should be in smaller sections than it appeared the OP was saying it would be.
??I don't think you mean the POURED section need be square, only that the control joints should be so.
Without knowing additional info as far as the sub-base characteristics, concrete strength, it is challenging to recommend a depth. But I am in agreement that 4.5" is on the low side.
Keyways for this application usually are for thicknesses of 10" or greater due to shear failure. Get rid of the keyways since it is redundant with the reinforcing steel.
Regarding the reinforcement, it is overkill. You can get away with a thicker slab and put the tiebars at the panel joints. Tiebar length are about 24" in length and centered down the outer panel perimeter that will tie into the adjacent panel. About every 24". Set at D/2 of the slab.
Zip strips, the plastic inserts, are not recommended for this application. You will need a full D/3 sawcut to achieve your best control joint. Best to sawcut within 12 hours of the pour. 1/8" minimum width.
The advice provided above is just that. I am a PE, but not yours. Ask around and see if you can get some pro bona work from a local PE familiar with roadwork.
Hope that gets you going in the right direction
Impossible is an opinion.
Yes, I am in agreement. This sounds like total brutality. Have you priced asphalt? Even with volunteers pouring concrete, I would think asphalt would be competitive.
EngineerGuy, I are one too.
That is why I recommended he get the standard detail for a commercial driveway in his locality, and build to it. They are typically well thought out and slightly conservative designs. I have checked a few against stadards, down through the years, and always ended up going with the standards. I also designed one as regional standard, about twenty years ago, that is still the standard.
Thanks for all the counsel on this. I am apprehensive about this, though it looks like we'll be starting next week. It sounds like we better seriously consider at least 5 1/2 thick. The rebars could then be cut back to what spacing? We do have a very solid base.It also sounds like you are saying we need to figure on letting the rebars stick out and into the next pour. We have a method of forming to do that - I was just concerned about having those exposed as a hazard to the concrete and people.Another question is about the striking off. I have never used a vibrating screed, but would it hurt the top to buy one of those cheaper ones that hold two boards and has handles. The strike off is the most brutal part for us.One more question, what about this invention found on Ebay: ?? Is this a joke or does it work? Tx
Edited 4/19/2008 2:18 pm ET by Fonzie
A power screed does not magically level the concrete. If you get too much in the forms, you will still have to rake the excess down. The screed won't simply flatten it. It's a beast to pull, though I suppose it is a bit easier than hand screeding. The main advantage is that it brings up a lot of cream which makes finishing easier.
when ever somebody says they are going to voulnteer, that means they are going o show up in $100 shorts and $200 tennis shoe, stand around and drink your beer, and still only one person be working. if you going to count on voulnteer you might as well do it yourself in five yards pours.it be cheaper in the long run to hire 20 people and pour all of it in one day.
"it be cheaper in the long run to hire 20 people and pour all of it in one day."Or the biggest mistake of your life LOL!I don't see any problem with pouring 10' strips with three people. I'd just tell the volunteers to stay 100' feet away and let them clean up when I'm done. I'd pour every other 10 slab, then fill in between them. I'd hang the rod out and have the volunteers put safety barriers up. If kids managed to impale themselves on them, I'd have the volunteers pull the corpses off the rebar before I had them move back the required 100'. I'm no concrete expert, but three of us could easily prep and pour 10' strips. I don't know how long they would be but 10' strips is easy basic stuff. Bob's next test date: 12/10/07
""I'm no concrete expert, but three of us could easily prep and pour 10' strips. I don't know how long they would be but 10' strips is easy basic stuff."" I have understood it to be 10' x 100' strips. roughly 2 two car garages .
They can't get your Goat if you don't tell them where it is hidden.
Oh....he's probably in for a heap of problems if he's thinking of pouring 100' and has to come here for advice. I hope he sends up pictures... I did see that he was worried about the screeding, which tells me he doesn't have anyone that can run a chute or anyone that has an eye for raking. If the chute man and rakers are good, the screeding is a walk in the park on a bullfloat and brush finish. I'd do 100' in a day, but I wouldn't have to come here for advice first. If I had to come here for advice first, I'd probably cut that amount in half till I got the hang of it. Bob's next test date: 12/10/07
You're right about the chute man, he can make it easy, or make it horrible.
There are two kinds of people who never amount to much:those who cannot do what they are told, and those who can do nothing else.
Thanks to all for all the advice. The two of us have experienced the gut feeling of hearing the concrete truck. We probably will hold back on the length until we get a "working model". I hadn't thought about separating the strips then filling in. That would save at least one form set up and the shoot would reach. We are finishing the roof tomorrow and will probably start some more serious planning. I am beginning to think it is going to need to be 5 1/2 inches thick as suggested. There has been enough strong advice on that we have to listen - especially since we have never done a parking lot before. What would you set the #4 rebars at - 3 feet apart?
1 foot by 1 foot
Go for the 5 1/2" of mud . The Engineer said you can skip the rebar ( not "Your" engineer , but the engineerguy ;-) ) and I agree. You have stated the gravel lot is 15 years old, by now it is as compacted as it is going to be. Set your screeds for the first pour, level off the gravel parking lot and compact any low areas with a "Jumping Jack " not a flat plate compactor.
Figure to pour every other bay. Use the tie bars as engineerguy recommended. Get some scrap lumber or ply to lay down on the tie bars for when the concrete truck has to drive into the bay to pour. Last thing you or the driver will want is a sidewall puncture from bar when he is there. As he backs out then lift the protective lumber and bend the bar back up. Some ways to set it up easily.
Start with strip #1, then follow with all the odd number strips in order.Then go back and infill the even numbered strips. Forms can be "jumped" and a good crew that thinks about it can make it happen quickly. Doing this will save lumber and expense.
Or set #1, pour, set #3, pour , small crew starts setting #5 while you and crew pour #2. This sequence may preserve some parking for you if it is an absolute necessity.
Also possible to pour just 50'out of the 100' using either method above then come back with the next 50' to finish up.
Don't forget cure or watering to keep the mud from drying out to fast . Last bit of advice: Don't rush this, the congregation will simply have to be patient about what it takes to do it right or they can donate to the " unofficial inspectors donation can" you will have set up to pay for the pros to do this.
They can't get your Goat if you don't tell them where it is hidden.
Thanks - the sub base has been compacted 50 years. I know we are taking on quite a challenge but the guy I work with has about 40 years experience and I have 43 - pouring concrete the first year of that. We have worked together 22 years. I have experienced the concrete "getting away", pouring with inexperienced help, pouring with warped bull float, clouds building, troweling out at 2 AM, a bicycle, calf, and kid in tennis shoes tracking across the driveway, etc. We will struggle through it. In 96 we lifted a house in the air and replaced the basement because we couldn't get a house mover interested. Two years ago we lifted a barn in the air - new foundation. We built a two story addition roof first (to protect complex roofs below), holding it up with buttresses. We were over our head on those too but we did it. How sure are you about the 5 1/2 (other views?), plastic covered and water cured, no rebar except on borders? This is Illinois (freeze thaw). I really like the sound of that though - is it a convenient revelation? I really hope we can do that. Rebar is a pain - it also would interfere with backing the truck in between strips. Is the curing the key on this?tx
Bit embarrassed here, it helps when the qualifications come earlier.
Your first posts didn't indicate experience of that many years in construction or concrete, sounds as if you have foreseen a lot of the potential problems.I would be pretty confident that the 51/2 is fine for a parking lot for cars.
One big issue is concrete always shrinks as it sets. It is best to cut the pour into squares if at all possible.
I don't know about the heavy freeze thaw cycles since my climate here in Ore. doesn't have them, My best advice on that is seek local advice on what is best.
Maybe talk to your batch plant and get some names of local concrete contractors or engineers, plead the fact you are doing volunteer work and need some input as to "whats best" & "what works" on the bar throughout the slab. I personally am a big fan of bar as I see it as cheap insurance, not only for load capacity but also to keep the concrete together in the eventuality it cracks . The increase thickness helps IMO. It is a pain , but if you do the "jump" forming method then the crew setting forms goes back and infills the even # pours with bar after the last odd # pour is made. Curing on concrete is always a key to reducing shrinkage cracks from occurring during the first 28 days or so. There are spray applied cures that will work and can be walked on the next day. All concrete crack according to some , the best thing to do is try to have it crack along predesignated lines (cuts) rather than uncontrolled cracking. Yes, the ties bars work to keep slab edges aligned with each other. I have done several big pours, the largest was done with 12-25' x 625' strips. A power screed was used for the job. All 8" thick and all with mats of 6-6-10-10 mesh in it,and tie bars at the pour joints. Each strip was saw cut into 25' squares after the pour was done. Trucks drove right onto and over the mesh in each "alley" as we went and then it was pulled up by a designated crew just in front of the mud.
They can't get your Goat if you don't tell them where it is hidden.
you need to dowel the slabs together
He's in Illinois, should those dowels be epoxied?
with the freezing ground you dont want one slab heaving higher than the surrounding slab, so by using dowels it keep them level
I mean the dowels themselves.
Sometimes up there in freezing country, you can see they use greenish colored rebar for bridges and joints on the roads.
Since his joints between pours are gonna be cold, held together by your suggestion, will these dowels need to be the greenish pre-epoxied type for best wear?
I was told the green coating on the rebar was a protective coating to protect against oxidation.
Guess BB can tell what's it's really for.
the green we use are for salt water corrision. unless salt is put on the slab, this will not be needed. you can epoxy but why pay to drill and epoxy. i would just place while pouring
These guys up north use salt on the roads and some parking lots for snow and ice clearing. Rock salt can be a big commodity some years.
http://cbs2chicago.com/local/road.salt.theft.2.652821.html
Back to the dowels. If'n I were to be pouring this lot, I'm thinking I'd be mixing up some 'poxy to coat any pieces of rod that get exposed in these joints. Especially since it'd be my labor having to do any repairs.
If you are in country with freeze thaw cycles, why aren't you blacktopping the parking lot?
with the amount of salt in use, you may find that blacktop would last longer.
Do not take this the wrong way but I really think you have taken on a job over your head.
From your questions you have been asking I get the feeling that you do not have the required experience to do this job.
You have volunteers that are willing to work but will they be willing to jump into the concrete with there tennis shoes on?
If I were you I would be letting the pros do this job.
Okay, I have had a few days to think about this and put myself in your shoes.
If you can provide me with the effective modulus of subgrade reaction, mean concrete modulus of rupture, drainage coefficient, I can give you a solid pavement thickness number. I already have in mind the load transfer coefficient, I will assume the estimated 18 kip equivalent single axle load (its a church parking lot, right), and the design serviceability loss. <grin>
Yes, this is what it takes for proper design of your highways and roads.
If it was me, with the information provided to date, 5.5" should suffice. But I would do as Jigs-n-fixtures recommends and inquire about typical thicknesses locally. I personally used to design roads and stream crossings for tanks and such, so my design are rather conservative. And I know my soil conditions.
Now if I was doing this job myself, with the labor force you have, this is what I would do:
Have a pre-construction meeting with your volunteers. Give them assigned task and if they aren't actively involved, have them waiting in a designated area away from the pour, but within yelling distance. Go through the task with them individually so that there isn't a question about what they are supposed to do. And do a dry run with them in the forms so they know what to expect and where to step. Make sure they know what to wear, since concrete mud is not mud and will not wash out after it sets.
If you can rent power screed equipment, do it and get familiar with it. Not the hour before the concrete truck shows up, but at least a day before. Do a dry run. Caress it... er, okay, just get friendly with it. Have at least one, maybe two other people get familiar with the machine. Also have tools/screed boards on hand in case your equipment breaks down.
Section up the pour into 10 sections at 10' increments, numbered 1 through 10. The first pour would be in section one and it would be a continuous poor. All 100' straight through which would be about 19 yards of concrete.
And that is all that I would do for the first day. This would give you a chance to evaluate your support crew, and tweak things if need. Also give you a chance to see if you will need hired help.
You don't say what type of forms you are using. I assume wood. 5.5" is right on for 2x6. Make sure they are set firmly and use kickers. String-line the edges as well. I personally hate wavy cold joints. One of my pet peeves.
For your tiebars that run along the continuos section of your pour, construct a rebar ladder with tie wire. Use a 9.5' length of rebar as the edges and tie the rung rebar to the edges. The rung rears will be your tie bars between the panels of your concrete sections. Suspend your rebar ladders from wire tied to the forms and wire chairs that suspend the tie bars at 2.25". The wire tie to the forms will keep the rebar from getting kicked out of place due to the concrete pour or being accidently kicked by a human.
For the tiebars between sections, drill a hole into the side of your form. Make it a little tight, but loose enough that you can get the form off the concrete and slip it of the rebar. You may even want to ladder tie one side of the tie forms (the side inside the form) to keep things aligned horizontally.
During the pour, I would have the truck drive right along the forms and pour in the concrete from a chute. No one even needs to step on or around the tie bars sticking out of the forms. Have at least two volunteers with a shovel and a rake to direct the concrete. Come behind with the screed. If human powered, have at least two teams, since the uninitiated will tire quickly. Get the mud to the surface. Float and finish. I assume broom finish.
Let set a day and strip the forms. Sawcut every 10' section to 1.75" in depth. This will form the control crack desired to these location. Let me emphasize with dovetail, either use a curing membrane or keep wet.
If everything and everyone works out, reset forms for section 3 and 10. Proceed as above. Then pour section 5 and 8 the following week. Followed by section 2 and 6. This would leave section 4 and 9 left as infill with only the end forms.
Dovetail, I took out the rebar the OP had at 2' oc since it was additional cost and not needed. Steel is getting costly with the international competition for it. The concrete panels with that thickness of concrete and the tiebars will act in conjunction with each other.
Regarding epoxy coated bar rebar, yes if possible and in budget, but only really needed at the tiebars.
Fonzie, slope of parking area is 2% minimum? I don't have the hydrology charts for your area, but whoever is caught parked in the low spot my be walking through an inch or so of water during a deluge. <grin>
Hope that helps.
Impossible is an opinion.
No problem . I don't have initials behind my name . What day does he pour #7 ? ;-)
They can't get your Goat if you don't tell them where it is hidden.
D'oh
Thanks for catching that.
With section 4 and 9.
Damn.... sometimes way too many things are going on.
And regarding the initials. I know of a lot of people with those initials that can design it, but don't have a clue how to build it. I grew up on a farm, and also had the hands on work in the field with my internship. So I have patched a road, worked the railroad track, built many a building, as well as dug and piped the trench. ;) Still lacking the finer points in the HVAC and sparky side of construction. But always learning.
Fonzie, one other thing. I would recommend a minimum 2500 psi concrete. The higher strenght, the better. Cost difference usually isn't that great. Again, not familiar with the locals capacity or capabilities.
Oh, and get a moderately stiff mix. Minimize water, but utilize plasticizers. The less water the stronger.
Impossible is an opinion.
Manards has a concrete curing compound 5 gal will do 1000 sq feet - 69.00 - is there a good/bad curing compound? I didn't ask if this was latex.I have asked around here about thickness, etc. The guy we are going to have do the back hoe work is a seasoned veteran we have worked with before (retired waterworks city guy), excellent with the backhoe. I have a friend that is the cement man's cement man I haven't got to call yet but will. He has done a lot of this.We are wanting to come up with a grade that preserves all our 50 year gravel base. It looks like we are going to plan to go with 5 1/2 thick, 6 bag, 1/2 rebar 2 ft both ways, sticking out to next pour. We cut upside down triangles under the holes and hold them on the form with plywood gussets. That makes it easy to remove the form.I assume we will have to stake with rebar.
six sack is a pretty hot mix, its a 4000 pushing a 5000
five sack 5 1/2 is plenty. if you pour wet you just throwing money away. no more than 4 1/2 inch slump
is curing compound curing compound or is there a difference?
What I know about curing compound is that in the last few years the really good and toxic stuff is only sold out the back door. Most that is on the market now is an acrylic based product and it does work. Read the instructions, this is not a case where more is better! brownie actually may have more and probably better info than I.
They can't get your Goat if you don't tell them where it is hidden.
curing compound (ha) the good stuff out the back door (must be like good contact cement vs the "safe vapor". as to pouring dry/wet I got caught up to the extreme once in pouring too dry and had to hammer the top smooth, it ended up over worked and crazed. It has to be workable when you just have a board to strike it off.
I really need a answer on this: A guy that supposedly pours every day that was in the concrete plant when I was checking on prices/delivery said I should rent a sidewalk screed (vibrator). I looked at it. It attaches to two 2x6 and has handlebars (that's the part I like, no down work) I would love to take care of the killing part of this with something like that but I'm afraid of it. It seems when you vibrate the concrete like that it transfers through the forms, also vibrating what you've already vibrated, causing down hill slump, problems. This guy said no, but it seems like I have read cautions on this. I am totally inexperienced on this - tx
Edited 4/23/2008 7:09 am ET by Fonzie
Those are crude tools at best. They've been around for 30+ years. A good wet screed is our tool of choice. You can rent them anywhere.
If you are pouring on a slope, you should start from the bottom or you definitely can get the concrete sliding downhill, especially if you are actually vibrating the forms.
Screed vibe
I know this is outdated but maybe it can help someone else. We recently purchased a screed that can be either a vibe screed or a manual type screed. You can stand and use it or adjust it down to a bunch of settings. We love ours and reccomend them to others. The screed is called apearms screed...they have a website but dont recall the URL think its screedconcrete.com or try apearms. We got a set and within a week ordered a second set along with the vibrating motor that was priced right.
When vibrating concrete make sure you understand what the aggregate is doing....you dont want it to settle too much and void the quality. Vibrating is good when you understand it needs to be a lower slump and not to stay in one spot too long. Spaling will happen quickly in freeze thaw areas if its over vibed. We tend to just wet screed and have best results. Thats what made the screed we mentioned so nice, it can be either. I think someone said a 4.5 slump? that is a good place to start only if you wet screed...if you vibe then a 3 inch slump and no wetter or problems are in your future. good luck.
Dan
Brownbag,I just bought a spin screed. Called, it is made in a city about 50 miles away - knew the guy. They were doing a demo yesterday, TV was there (using in a tunnel in Canada). He delivered mine today. I'll let you guys know how it works out and hopefully have pics. It's a different principle - check it out:http://www.spinscreed.com/
Please don't forget to tell how it works out. It seems almost to good to be true.
Did you check out the video on their website? pretty impressive. Just google: spinscreed The demo video is offered on top. I missed it the first time.
I saw it and the other one to. Just wondering how it really preforms.
I have used them before, they are great. one I used had a hydrulic pump to spin it. fill the tube with water and it =can do a three inch slump perfect.
I've seen those type of rollerscreeds on highway projects. I didn't realize they did anything but roll by pulling them. Bob's next test date: 12/10/07
...and put grease or paper on the ends of your dowels before the next placement to allow lateral slippage.
I am a PE, but not yours.
I was always wondering what field-------- I'm going to pick your brain next year for a geotech, & advise on one wall of my shop that will be cut into my hillside------ so don't go runnin off ;-)
“The world is a dangerous place, not because of those who do evil, but because of those who look on and do nothing.” —Albert Einstein
Now that your buried with advice, I'll add one more detail:
I suggest you make the pour from a line pump on that large a pour if you're going to place reinforcing in the concrete.
Backing a truck in over placed bar or wire can create some problems, especially if you use reinforcing wire. As often as not, the drivers on the truck can grab the wire and start pulling it around the tires.
Hey, you guys really steered me right increasing the thickness to 5 1/2. The pour went great. We used 208 yd of 6 bag mix, 13000 ft of #4 rebar, and went through 3 diamond blades cutting every 10 ft 1 3/4 deep. For cutting I used a circular saw with a small hole drilled above the blade, a aluminum straight edge and a small water pump.
We applied the curing compound with a long handled roller (I like that method, even coverage) fairly quickly after pour.
The big news is that the Spin - Screed (you can google Spin Screed for demo video) worked great! The guy that makes this particular model used to live in this town - now about 50 miles away. I gave him a call and he delivered it (I bought a 14 ft model) within 2 days.
Justin Fink let me write a review for FHB (latest issue) on the Spin Screed. He was a lot of help with the article, very encouraging.
I really recommend this Spin Screed. Only 2 of us had essentially poured concrete (the guys running the screed had never poured, yet caught on right away).
After the first day which wasn't too bad, but harder since we were pouring up against the building we were able to pour 12 x 112 strips (24 yd) with ease. One day we stripped forms, placed and tied rebar, cut previous pour and poured the same day. One day we had a funeral dinner at the building and still poured a strip.
One thing that gives me a lot of satisfaction is that it drains perfectly - there's not a "mud-hole" in it. The water just gently flows off just where we planned (sorry if it's bragging, ha).
I had to hold off on this thread since the Spin Screed tool review was in process. Here are some pictures.
Edited 10/5/2008 6:48 pm ET by Fonzie
Edited 10/5/2008 10:13 pm ET by Fonzie
Man, that's just super - congratulations on that.
Forrest
Looks extremely good. You're a flatwork contractor now. What're you charging per foot?!