[TowerTalk] rebar DOES cause concrete spalling

FireBrick w9ol at billnjudy.com
Thu Oct 12 07:54:54 EDT 2006

That was my business. I was one of those guys, you saw on scaffolds hanging on the side of 
buildings repairing concrete, stone, and masonry.

I was a Chicago licensed masonry contractor.

Even on the sides of concrete buildings, rebar, too close to the surface would adsorb 
enough moisture through the concrete to rust.
Rust can cause rebar to increase it's size 11 fold.
That would cause the concrete to spall off, exposing more rebar etc. etc.

I don't know if that's empirical, actual, or just "been dere, made lots of money fixing 
it" evidence.

Now how long before the bottom of the concrete base spalled off to cause problems 
certainly depends on many factors and I can't predict.

But moisture contact with rebar will cause rust, and will cause concrete to deteriorate.

Cat's Favorite Game - "Ha! Made you look!"

Bill H. in Chicagoland
webcams at
weather at http://hhweather.webhop.org

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