Concrete Damage

[Yardworks]

We had some good ice/snow storms the last couple weeks which left quite a build up on the sidewalks of some of my customers that do not want salt used. Well I pushed the idea of some salt just to get the sidewalks back into useable condition. I use magic salt and told them it would not be as hard on concrete as regular salt and all the other benifits. I applied salt one day and scraped them all down to concrete the next. Everything worked great except 3 of the 84 sidewalks I did this to had severe salt damage from this one time. They were acually a little mushy. I have never seen anything like this before. So the big question is how to fix the problem. Is there any way to resurface/recoat the concrete without tearing out the old and replacing everything. Any imput or ideas would be greatly appreciated. Thanks, Jeff

 

[WALT]

Not much you can do

Sad but true, the options are very little. For a temp fix that will for sure fail because it won't bond will be to put a thin surface layer (mortar). You may also want to use a grinder lightly to make it an even, uniform surface. This may also result in a smoother finish and loss of traction.

Because this only happened to 3 of 84 sidewalls could be either poor finishing (too much) causing too much paste to be at the top, and creating that "mushy" surface you stated, thus a weak top layer. This also reduces the amount of air in the mix as it's placed. Every once in a while the plant will screw you on a mix and not put enough air in the mix. Or it could be old and over time with the freeze/thaw effect on the concrete.

Another thing, Were the sidewalks fairly new? I say this it is reccomemmed not to salt the first winter the crete was poured.

I hope this helps...

 

[66Construction]

Yard Works

I would wait and see if the owners realy break your stones over it or let it slide it's only 3 out of 84. Walt is right it sounds like this wasnt your fault it was whoever poured the sidewalk. If you finish concrete before that finishing window comes along everything that would have bled to the surface as the concrete sets gets traped under the finish and will actualy separate them, only a hair but enough for some salt or something to cause major damage. Resurfacing probably wont last unless you do something like take the top 2" off and drive nails through mesh and pour over it. Leave the nails up about an inch and use the mesh that is for resurfacing foundations. I have had "some" luck with this on steps. If you do this dont use a mortar use something that was meant for this a top and bond or a sand mix and add extra portland, the hogher psi is what will keep it there. It would probably be easier and less time consuming just to cut the sections out and pour new ones. It will definitly last. Good luck depending on the client this could be a walk in the park or a nightmare.

are these city sidewalks? that can change a lot.

 

[thelawnguy]

"Walt is right it sounds like this wasnt your fault it was whoever poured the sidewalk"

Sure was his fault! The customers specifically asked that salt not be used: "...some of my customers that do not want salt used. Well I pushed the idea of some salt just to get the sidewalks back into useable condition." Why is it so difficult to listen to the customers wants and instructions?

Im not picking on Yardworks but it sure illustrates a valuable lesson to the rest of us.

Now you know why its called Magic; darn near made the sidewalk disappear LOL

 

[Yardworks]

I was wondering if it could be a problem of how the cement cures. The three sidewalks that the damage occured on were the ones that never see much sun. They are tucked way back against alot of trees. This is the only thing that is different from the other 81 sidewalks. The same company poured all the sidewalks. Bill, I guess the word pushed is actually a little strong. I suggested to the people how I could get the sidewalks back in good condition and they agreed something had to be done. I guess I will either pay to have them replaced or if it is to much my insurance company will have to take care of it. Thanks for the info on cement procedures and possible fixes. I was hoping there was a finishing product that would be an easy fix and not so expensive. Oh well. You win some and you lose some. I will make the prospect of cement damage more known the next time I suggest salt to people that don't like salt. I was a little overconfident with the magic salt. I'm about the only person in my area that uses it and I thought it was a cure all. It sounded like it would be harmless on concrete. Now I can't wait until spring to see if it's claim for being beneficial to grass and plants holds true. I guess when it comes down to damages, salt is salt.....

 

[GREG R]

We use calcium chloride on all of our sidewalks
and all of our concrete parking lots,
and it works down to -25 degrees and heats as it
melts, so you use less than salt.
Sure its expensive ($11.58 per 50lbs)
but I do believe it's concrete safe.
Since nobody has suggested this yet,
mybe I'm wrong...I've only been doing this
for about 9 yrs..
Call one of the local concrete contractors and see
what thier solution and estimate is before you worry
yourself into a nervous break down..hope it works out
for you

 

[66Construction]

The shade I dont' think would effect it much atleast not in a bad way. If anything I would think that it would keep the sun off of it which would slow the hydration process making it stronger.

However if the concrete in the shade was finished at the same time as the stuff not in the shade which would have set up faster due to the sun being on it....well you know what happened.

 

[n y snow pros]

Now i am not here to state magic salt is safe, but it is safe when used in the recommended amount on concrete.The bagged magic is produced at 4 gallons to every ton of salt vs bulk magic which is 8 gallons per ton.Think about it that means there is 1/40 of a gallon per 50lb bag.If you over apply anything you can run into problems .For example a plant needs water to survive but you dont submegre the plant in water or you will drown it how come it needs water!My point is 1st you cant garuntee concrete you didnt pore or make because of the inconsistency of its quality.2nd if you apply the correct amount of product that is needed you should not have a problem.Calcium is by far the worst thing you can apply to concrete and we were always a big user of it until we found magic.Calcium is air temperature controlled and this is why an unused bag of calcium turns to rock as it sucks all the moisture out of the air.this in turn is what creates several premature concrete failures do to freeze thaw cycles.Magic is ground temperature controlled and therefore does not cause nearly as many freeze thaw cycles.Personally if the customer said no salt i would have told him about magic straigjht liquid with no salt,in your defense it sounds like the concrete was of poor quality how else do you explain the damage to only 3 sidewalks.If this was also done only once then there was considerable damage prior to applying magic.there is no possible way one application especially if you swept the walks clear after its use that the concrete was damaged from magic salt.
John P

 

[plowjockey]

Yardworks
You stated that the sidewalks were all poured by the same contractor. If you know the person then maybe you could talk to him and (oops politically correct or her) find out if there was any different procedure or obvious timetable difference in the pouring of these sections.

Just my 0.02 cents worth

Bruce

 

[Dusty]

You might think of having the damaged sidewalks sandblasted. It might be a less expensive method to restore the top surface than replacing.