Repairing Crack in Concrete Deck Pier

[mooredaniel1]

I set this pier a couple weeks ago for a deck extension. I noticed this hairline crack wrapping 3/4 around the pier about a foot from the top. The crack starts from the string I left inside to keep the rebar straight, so maybe that was the cause? First time pouring so lesson learned I guess.

Wondering if I should patch with mortar or use an epoxy like below. The crack is only 1/8th at the largest point.

Crack-Pac®

FYI I’m hoping to repair because the deck extension this supports is very small (24 sq ft, and not expecting big loads more than 400 lbs.) and I can add a deck footing block or two if need be. Will be showing the inspector.

Thanks for any advice.

 

[billshack]

You have rebar inside ? then you should be ok

 

[mooredaniel1]

Thanks. Yes, three rebar run from the footing to a few inches from the top of the pier.

 

[bud16415]

I would skim over it to keep water out with a product called CementAll can be found at builder centers and if you google there are videos of just how to use it in the Home Depot site. With the rebar inside I also wouldn't worry. Next time don't use the string.

 

[mooredaniel1]

Thanks for the suggestion. That looks perfect for the job.

 

[bud16415]

Thanks for the suggestion. That looks perfect for the job.

YW

I would take my 4" angle grinder and open up the crack a bit first and get any lose material out then fill the crack. The more surface area you contact the better the fix.

 

[tomtheelder2020]

The repair is to keep moisture out - it won't affect lost strength (if any). So rather that a cement type patch that will be brittle and might crack again, I would use a flexible epoxy that will hold tight but can accept some movement. I have been using the product from Total Boat, but plan to try this next: Pettit Paint Flexpoxy - Flexible Structural Repair Epoxy - YouTube

Also, for your next project, I think there is a reasonable likelihood the crack occurred because your mix was too wet and the concrete shrunk as it cured.

 

[BuzzLOL]

The repair is to keep moisture out - it won't affect lost strength (if any).

Moisture getting into concrete cracks and rusting out the re-rod is what recently caused the giant apartment building in Florida to collapse killing 150 people...

 

[tomtheelder2020]

Moisture getting into concrete cracks and rusting out the re-rod is what recently caused the giant apartment building in Florida to collapse killing 150 people...

My meaning must not have been as clear as I thought. The repair wont affect whatever strength was lost due to cracked concrete. Moisture getting in to rust the concrete is the concern - which is why I recommend using a non-cement product that is less likely to crack in the future.

 

[BuzzLOL]

My meaning must not have been as clear as I thought.

I understood... was just giving a recent big example of what can happen when cracks aren't resealed...