Concrete drive

[mjncad]

Nice place you have Chris.

Tractorshopper:

If you're going to spend $4,700 for asphalt, spend another $300 and get concrete.

 

[scoutcub]

A few weeks ago I got a bid for 12' X 180 ft driveway up a gravel slope, with a landing in front of the garage, all prep work w/rebar except I lay the gravel. He's using 4-5" with 3 "footings" .....being a steep driveway, he will dig down and pour some 2' footings, or bases to support the entire driveway. $9800.
Around this area concrete is down to $80 per sq ft, and asphalt costs have risen to about the same as concrete.

 

[tractorshopper]

Nice place you have Chris.

Tractorshopper:

If you're going to spend $4,700 for asphalt, spend another $300 and get concrete.

No brainer isn't it:thumbsup:? Haven't talked to any other asphalt guys to check that price, but couldn't believe it was that close.

 

[Dargo]

My driveway is just over a 1/4 mile long and all concrete. This is in addition to large parking areas as well as nearly 2500 sq. ft. of concrete patio areas around my home and pool. In addition to all that concrete, I have a 60X60 barn and 80X120 barn concreted. I've been involved in every pour. I've learned a lot of good information as well as some very bad advice given from "professionals". Those "professionals" were taken to court and had to remove their work and pour it again to my specifications.

First off, I'd never, ever consider a 3000 psi mix; especially at only 4" thick! If you watch, you won't even get 4" of concrete either. Most companies use 2X4's for their forms. If so, you're only getting about 3 1/2" of a very weak mix. Also, based on much experience at tearing out existing concrete, the fiber mesh is a complete and total joke!! I can tell no difference in tearing out a pad with no support, wire, rebar or mesh vs tearing out a pad "reinforced" with fiber mesh. It offers no additional strength! With a very weak mix and only 3 1/2" of concrete, you'll have it all busted up within 5 years if you only drive bicycles down the driveway!

Trust me, I've spent many tens of thousands of dollars on concrete work. Not all was well spent because I took the advice of people "selling" a product rather than helping me. Since I assume that you only plan on doing it once, if you have any vehicles that weigh more than 4000 pounds going up and down your driveway, I'd go with an absolute minimum of 5 1/2" (using 2X6 forms) with 5000 psi mix and sheets of rebar matting. Rather than the almost worthless roll out thin wire for support, the rebar matting I speak of is made of either 1/4" or 3/8" rebar that is made in 8'X10' mats. They sit on specific 'hats' that keep them in the middle of the concrete.

The 1/4 mile part of my driveway was made with 6" of 5000 psi mix and the 1/4" rebar mats except the bridge part. It is 14" thick and has nearly 4 tons of half inch rebar welded in place and a 5500 psi mix. After my driveway was finished I put in the larger barn the next year. It took nearly 240 yards of concrete to pour the floor of that barn and each truck ran up and down my driveway without causing any damage.

Where I live, asphalt driveways are quickly destroyed if there is any heavy vehicles on them on the hot summer months. My mom's driveway was gone in 5 years just from their trash truck, UPS trucks and FedEx trucks. It's far more expensive for concrete, but I never plan on doing it again. Unless you plan on doing yours again in 5 to 10 years, I'd strongly suggest using a thicker pad, good steel reinforcement and a much stronger mix. As the old saying goes, you can pay now or you can pay later. If you pay later, you get to pay twice along with the expense of tearing out what's left of your first driveway. If you want, I have plenty of pictures of the processes being done. I got much, much better information from "commercial only" concrete contractors than the little driveway getters. Since my driveway and other areas were so large, it cost me less and I got a far superior job done by the commercial guys. They laugh their rear off at some of the little concrete contractor's suggestions. It's your money. Spend it wisely!

 

[EddieWalker]

Dargo said it very well. This is excellent advice from somebody who has been there, done it and had to redo it.

I would never use fiberglass for strength. It was not designed to replace metal, and it is not capable of replacing metal. For those who have it and feel that it's doing hte job of metal, congrats to you, but what is really happening is that you just have a very good base and the concrete is not stressed. If fiberglass really could replace steel, it would be used all the time. It's not, and the reason is that rebar does the job better then anything else out there.

Eddie

 

[ctgoldwing]

This article might answer your question. I have used both. Wire is tough to handle, and must be placed on hangers. Fiber is a no brain er

http://www.nycon.com/pdf/NyconvsWWF.pdf.

Doesn't appear to be an idependant unbiased opinion to me. Also his credentials are a little, ahhh, lacking:

About the Author:
Robert Cruso , Nycon痴 executive vice president, studied Engineering and Construction Sciences at Roger Williams University in Rhode Island.

Does this mean he took a one week short course? There sure isn't any degree mentioned. If I wanted to be considered a 'source' of information on this type of product I sure would be more reassuring with a BSCE or BSME after my name - just saying. . .

 

[dodge man]

Dargo is by far giving you the best advice, although I can't agree with everything he says.

First off I would say a 4000 psi mix would be adequate, he is correct, 3000 psi is a joke.

Second, 4 inches thick is not thick enough. I agree with him 5 1/2 inches is a minumum.

I have a 5" slap in front of my garage that has no rebar or wire mesh but it has the fiber reinforcement. It does help, but I'm not kidding myself, if something heavy drove across it, it would crack. The fiber just helps with the shrinkage cracking, and it can help a lot in that regard. The corners of concrete are what is always vunreable to cracking off without rebar in it. If something heavy drives across a corner, it is a sure bet to break off.

Asphalt can do a good job, my driveway is about 900 feet long asphalt, and about 10 years old. Its got maybe 2 to 5 years left before I have to have it resurfaced. Its also alot of work to have to seal it every couple of years. When I had it done, concrete was a lot higher, but the price of oil has driven the price of asphalt up, so they are a lot closer than they used to be. Ashpalt can give you 10 to 15 years of use if done correctly.

The best advice I can give you is that 4 inches thick is not going to get the job done. In perfect conditions it might, but it ends up a little thin in places, and if the subgrade isn't perfect, it will fall apart. As others have said, mesh ends up in the bottom of the slab, rebar won't. If done correctly, you can get by without rebar or mesh, but the slap has to be thick enough and you have to have enough joints cut in it to make up for no reinforcement.

I work for a civil engineering company and have seen thousands of yards of concrete poured for anything from streets to sidewalks, to footings, stuctural concrete, deep piles and caisons etc. Even if every thing is perfect, things can still go wrong. We always test the concrete for air content, slump (not to wet), and strength, by taking test cylinders. All that said, when I hired someone to pour my garage foundation and slab, I just cut the guy loose and just let him do his thing. Just make sure its a good contractor.

 

[hawkeye08]

I had no time, but wanted my 40x60 shop done. I paid to have the shop built (never again) and had the floor poured (never again).

If I was doing it over, I would build my own shop (better quality for the money) and prep and pour my own concrete floor (with compacted crushed gravel base and rebar). I got talked into fiber, no rebar and pea gravel for base. What a laugh they must have had. Bad advice from people I trusted. The internet makes research much easier. It is not all bad, I have dry storage for all my junk.

I have cracks (at least they are mostly where the inverted plastic tees are).

Around here, concrete is considered a permanent addition (and adds to property value and taxes) and asphalt is considered temporary. I would like to pour a 24' slab in front of garage though. It will be 5 1/2" with rebar with compacted crushed gravel for base.

 

[mjncad]

Good Lord Dargo! That's a lot of concrete at your place! When I spec'd out the concrete for the estimates I received, I specifically wrote in my notes that the slabs shall be a true 6" thick, not a nominal 6" as defined by a 2"x6" piece of lumber. If that means they have to rip boards to get the thickness I want, so be it.

Now if I could only afford to have the work done.

 

[Cat_Driver]

Fiber is for shrinkage cracking at the surface. Period. It serves no primary reinforcement what-so-ever.

Sorry but fibers do add strength to concrete. You've even answered that concern in your response. the fact it reduces cracks tell you it adds strength because cracks cause LESS STRENGTH.

I won't go into the engineering here because there is a ton of facts on the net.

I would use stainless steel fibers which they uses to reinforce bridge columns in earthquake areas.

Carbon Steel Fibers Product Profile

A normal size fibre for European shotcrete (1 mm diameter, 45 mm length耀teel or "plastic") will increase the concrete tensile strength.

Steel is the strongest commonly-available fiber, and come in different lengths (30 to 80 mm in Europe) and shapes (end-hooks). Steel fibres can only be used on surfaces that can tolerate or avoid corrosion and rust stains. In some cases, a steel-fiber surface is faced with other materials.

Glass fiber is inexpensive and corrosion-proof, but not as ductile as steel. Recently, spun basalt fiber, long available in Eastern Europe, has become available in the U.S. and Western Europe. Basalt fibre is stronger and less expensive than glass, but historically, has not resisted the alkaline environment of portland cement well enough to be used as direct reinforcement. New materials use plastic binders to isolate the basalt fiber from the cement.

The premium fibers are graphite reinforced plastic fibers, which are nearly as strong as steel, lighter-weight and corrosion-proof. Some experiments have had promising early results with carbon nanotubes, but the material is still far too expensive for any building.