Scaling and Mortar Flaking of concrete slab on ground

[Localeng]

The concrete sidewalk is exposed to snow in winter and extreme hot in summer.
Yes, here's Texas, but the sidewalk is located on the mountain, where has usually snow in the winter.
Because of freezing and thawing, the sidewalk has severe scaling and mortar flaking problem.
Especially, it happened at shade area.

Any idea of repair the sidewalk?
PCA recommends applying 'breathable surface treatment using linseed oil, silane, and siloxane.
And, they don't recommend using epoxy because it's a impermeable material that can lock up moisture which can freeze under the coat.
If you can share your experience of repair the same problem, that'll be greatly appreciated.

Thank you for sharing your idea and experience!

 

[bridgebuster]

A sealer won't improve the appearance and won't prevent further damage. The first step is either replace the damaged flag or repair the surface - Sika has various products - then apply the sealant; silane sealer works well.

 

[JAE]

If it is just a sidewalk - tear it out and start over. You can try to chip out the top sectons of the slab and put back a bonded overlay but that would be more work and money than just replacing it.


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[Ron]

Agree with JAE

 

[Localeng]

JAE and Ron ---
Thank you for sharing your idea.
Yes, that's right. It's just sidewalk, but the square footage is not small.
The scaling and mortar flaking problem are limited in small sections now, but the rest of huge areas have started showing flaking problem. I'm pretty sure those areas will have same problems of scaling and flaking pretty soon.
The cost of replacing all these section won't be cheap at all.
I may replace those scaling and mortar flaking areas, but the rest of huge areas require some other solution to prevent further deterioration.

Any other idea?

 

[JAE]

The choice of repair option based on cost should be based on the comparison of the cost of replacement vs. the cost of other options.
The other options, in my view, would all be more expensive than replacement assuming you have to treat a majority of the surface area going forward.

Grinding and bonded overlays - or even patching - are going to be labor intensive and only band-aids to the root problem.


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[Ron]

Agree with JAE....again!

 

[darthsoilsguy2]

that photo looks like the problem is not the environment, but the way it was originally finished. I would suspect that the surface was worked by the concrete crew while the bleed water was still on the surface..... or a rain storm they didn't see coming showed up and they worked rainwater into the surface..... or it was very dry and hot and they couldn't work the concrete so they put a lot of water on the surface to work it.... you see a theme here.

agree with others... but since the Owner may want to give polymer-modified resurfacing a shot, especially since i imagine the door is closed on getting the original contractor to replace at no cost. FYI, don't put yourself in the position where you guarantee resurfacing will work. it is a band-aid and experiment, and there are plenty of people with horrible experiences with it to counter the people that love it. if the Owner really wants a resurfacing option, i would try to convince them to tackle the worse area as a guinea pig and see how it performs after a year (or more) before expanding the scope. If it doesn't work they will really want to rip it out, not to mention that the resurfaced area will look different too and there could be buyer remorse from that too. maybe 1000 sqft of slab and grouped into 1 area. definitely get rip-out replace quotes to compare with. the surface will need to be hit with a scabbler (not just pressurewashed) to take off that poor finishing if what i suspect is true. i would look at getting prices for any resurfacing approaches from waterproofing contractors and prices for any demo/rebuild from flatwork contractors.

 

[JAE]

don't put yourself in the position where you guarantee resurfacing will work. it is a band-aid and experiment

Yep.

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