I need some advice. We poured a concrete deck. in 1997.The concrete was dyed red and was sprinkled with a black substance and then stamped to look like cobblestone. Our steps and back deck were poured on one day.
The big deck that surrounds our steps was poured a couple days later. The big deck immediately started chipping. We were told it is because of the shale in the concrete.
They called it shale pop.
They told us it would not chip anymore and would be O.K.
Today our deck is getting more red by the day. The steps and our back deck are fine, and the big deck has a lot of chipping.
We have had them look at it, and they try to make up excuses. What should we do?

Please help me.

If the thing they call "shale pop" is what we call "aggregate Silica Reaction - ASR" then you have a problem.

The good news is that it is very simple to verify whether the problem is really ASR. (and it sounds like it). A concrete Petrographer can identify it easily under a microscope.

The bad news is that they are wrong. It will not stop chipping until all the reactive particles in the concrete finish reacting. In many cases it may result in unusable concrete.

The normal standards of practice require the Ready Mixed Concrete supplier to test the aggregates and never use reactive aggregates (such as shale).  When they happen to use some, they should take full responsibility and replace the concrete. In my experience, once the presence of ASR was established, the supplier would replace it at their expense.

The contractor may not have been able to prevent it, but as the one who sold it to you is contractually responsible to you, and should get the supplier to replace the deck.

You may wish to consult the building department at your locality for their experience with similar problems.

By the way - where are you located?

To learn more you may search the Web on "ASR Concrete Aggregate.  "Compare the photos and information you find to your situation.

Good luck,

Please forgive me, but I forgot what your title was? I think I found your address in concrete doctor?  Is that correct? Where would I find a person to test our deck for ASR?  I am not sure where to go from here.

I REALLY APPRECIATE any help that you can give me.

Find out who does the concrete testing in your area. I could not find in the Yellow Pages, but check with the Ready Mixed concrete supplier (Is there only one? Did they sell you the concrete?) and the building department.  In Fort Dodge that would probably be at 515 573-2323.

The code requires that concrete be tested - so someone must do it.

If you cannot find one nearby, try calling "Pella" at 515-628-1357 and ask who they use.

Or call any of these laboratories (I don't know if they test concrete):
Geotechnical - 515-270-6542
American - 319-326-4847
AMI - 515-274-3996

Your best bet is probably to call Kevin Macdonald at 612-942-4826.He is the VP of the Iowa-Minnesota chapter of the American Concrete Institute.

Good luck

It was suggested to us to build this type of deck from an employee of JB.  We thought it was a good idea, because we wanted something that was different, with low maintenance.  We went to DJ, and he told us that yes indeed his company could build one. Mr. J quoted us the price and then all materials needed Mr. J purchased.  I am not sure but I think that there is only one concrete supplier. I am going to check that out further.