# stamped concrete damage/repair?



## dynamo (Feb 22, 2009)

hello, we moved into our present home last summer.
it is approx. 11 years old and has stamped concrete (dark grey/black colour) for the driveway and around the house.
the driveway is getting pitted.
the previous owner, prior to sale, had applied what looks like tar to the affected areas.
i've attached some pics in hopes that someone has similar experience on how to repair these pitted areas if possible.
alos, what would be the causes of this pitting; e.g. shovelling snow, using salt, etc.?
what about using sealer after repair (if possible); would it make the drive slippery when wet?
it gave us a little hard time with ll the snow this past winter (we use a plastic snow shovel, no salt).
thanks in advance for any suggestions/ideas.

regards,
george.


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## Canarywood1 (May 5, 2012)

The next to last picture looks like the concrete is spalling or scaling ,and the cause of it could be from improper placement and finishing, or possibly salt intrusion, may not have been sealed , just a few of the things that could have happened, as to a fix i'd say kind of iffy.


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## Mort (Nov 26, 2008)

It could be de-icer, or poor placement methods when it was first constructed (too much water added, bad weather, or any number of factors).

***EDIT*** Seems Canary beat me to it, glad I wasn't offering crappy advice


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## dynamo (Feb 22, 2009)

Canarywood1 said:


> The next to last picture looks like the concrete is spalling or scaling ,and the cause of it could be from improper placement and finishing, or possibly salt intrusion, may not have been sealed , just a few of the things that could have happened, as to a fix i'd say kind of iffy.


thanks for the quick reply, Canarywood1.
i guess i`d better hurry and seal it to salvage what is left, or an other ideas welcome


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## dynamo (Feb 22, 2009)

Mort said:


> It could be de-icer, or poor placement methods when it was first constructed (too much water added, bad weather, or any number of factors).
> 
> ***EDIT*** Seems Canary beat me to it, glad I wasn't offering crappy advice


thanks Mort, appreciate your time and suggestions!


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## Canarywood1 (May 5, 2012)

dynamo said:


> thanks for the quick reply, Canarywood1.
> i guess i`d better hurry and seal it to salvage what is left, or an other ideas welcome


 

More than likely to late for that,damage has been done.


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## concretemasonry (Oct 10, 2006)

Two comments -

1) Everyone missed a very possible cause of the deterioration. There may have not any air entrainment used in the concrete. Our climate is probably very similar to the original poster's climate. Here, all exterior concrete for city, state or municipal work must be air entrained. The larger ready-mix suppliers will not allow non-entrained concrete to be unloaded if it appeared it is for a similar exposure - they gladly will provide the names of the small suppliers that will sell anything. Apparently, it is cheaper to lose the sale instead of being drawn into disputes were non- air entrained concrete is used.

2) There is a bit of a pattern to the deterioration and those areas are generally along the line of tire tracking and dropping of salt laden slop, ice and debris.

The cost of the air entrainment is minimal (not a profit item), but is proven benefit.

Dick


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## dynamo (Feb 22, 2009)

concretemasonry said:


> Two comments -
> 
> 1) Everyone missed a very possible cause of the deterioration. There may have not any air entrainment used in the concrete. Our climate is probably very similar to the original poster's climate. Here, all exterior concrete for city, state or municipal work must be air entrained. The larger ready-mix suppliers will not allow non-entrained concrete to be unloaded if it appeared it is for a similar exposure - they gladly will provide the names of the small suppliers that will sell anything. Apparently, it is cheaper to lose the sale instead of being drawn into disputes were non- air entrained concrete is used.
> 
> ...


Thanks Dick.
Obviously, you know what you`re talking about but please pardon my ignorance, it`s mostly sounding Greek to me.

Are you saying the concrete used was not properly treated prior to install?
The rest of the sidewalk/patio is fine and loos great, IMO.

Is there anything I can do now to improve/maintain the damaged area?
Should i seal it now or after repairing, if there is a repair?


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## Mort (Nov 26, 2008)

I feel I must disagree, partially, with my esteemed colleague, Mr. ConcreteMasonry. But first, let me translate Concrete-ese into English. 

All concrete has tiny air pockets in it naturally, which make up between 1-3% of the volume. In order to allow concrete to expand and contract when it freezes and thaws outside, that air percentage needs to be closer to 5-6% of the volume of the concrete. Fortunately, there is a chemical that will do that, in the right dosage, and everything will be peachy. 

Where I disagree with Dick is that air entrainment is the best thing for concrete companies' profits because they can basically sell 5% more product without adding any more cement, sand, etc. There would be no advantage to them selling non-air concrete where air concrete is needed. The quality control, however, would be suspect, as smaller companies would get it right initially and just assume everything would always be the same, and concrete isn't like that. 

To the OP, there are ways to tell at this late stage whether it had the proper air entrainment, but I don't believe it to be worth the expense.


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## Canarywood1 (May 5, 2012)

"Are you saying the concrete used was not properly treated prior to install?
The rest of the sidewalk/patio is fine and loos great, "


What he's saying is the concrete was not air entrained, when a contractor orders concrete, he needs to state to the order taker that the concrete will be used for, any concrete used in the construction of sidewalks, driveways, curbs, patios, in other words anything poured outdoors should be air entrained, if not you run the risk of spalling, which is what I think you have.


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## concretemasonry (Oct 10, 2006)

Canary is right about almost universal use of air-entrained for exposed concrete where there are freezing temperatures. Even some parts of the U.S., with cool temps and moisture (rain/snow) can have more freezing/thawing cycles with moisture than the bitter cold areas.

The $ difference is only about 3.5% (difference between the industry assumed 1.5% air for normal concrete and the 5% for entrained air and that applies only to the aggregate part of the mixture and cement cost per yard is probably the same because many suppliers need to use more cement per yard for air entrained concrete. The cost of the air entraining agent (a glorified soap) is not too much, but it adds up.

One of the biggest single costs in concrete is the delivery because of the truck cost, operating expenses, maintenance and driver costs. That does not include the cost of money to buy or have tied up in a $125,000+ truck. The trucks on the average in many areas do not run every day. Somehow putting a $40,000-$60,00/year driver (cost with all benefits and tax) into a high maintenance vehicle just to spend 1 or 2 hours (loading, driving to, unloading, washing out and driving return) to deliver $1250 of material. The expensive truck is essentially uncontrolled since it is directed by the contractor that makes the access and says where the driver should go, unload and wash out.

Some people in the aggregate and ready mix business describe the ready mix portion as being the most expensive possible way to sell aggregate. Aggregate can be produced at a scheduled rate and inventoried easily, but ready mix takes a lot of extra money and it cannot be inventoried, but enough capacity to satisfy the hourly needs/demands and you cannot hire extra trucks to deliver ready-mix.

Dick


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## Canarywood1 (May 5, 2012)

Dick is right on most things, but the cost of a new Mack truck and bridge formula mixer, today is $185.000, and if on a given day equipment is available, it can be hired out on a daily basis.


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## concretemasonry (Oct 10, 2006)

I used the lower price for common/typical truck and not a tag axle with high capacity that the big volume producers need for commercial jobs with big pours.

Dick


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## Canarywood1 (May 5, 2012)

concretemasonry said:


> I used the lower price for common/typical truck and not a tag axle with high capacity that the big volume producers need for commercial jobs with big pours.
> 
> Dick


 

It's the only kind we have.


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## Msradell (Sep 1, 2011)

Canarywood1 said:


> Dick is right on most things, but the cost of a new Mack truck and bridge formula mixer, today is $185.000, and if on a given day equipment is available, it can be hired out on a daily basis.


I'm assuming the Oshkosh rear engine, front discharge mixers are even more expensive? That's about all they use around here.


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## Mort (Nov 26, 2008)

Yeah, I think they're right around a quarter mil, if I recall correctly.


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