Seperation of steel from concrete

[m1208]

I am working on an old house with steel floor girders and metal support system (raised foundation). Some of the metal support system has corroded over the years due to moisture from the concrete and metal not being galvanized. I am pouring new concrete on top of existing concrete footing and installing a new metal support system. I plan to put a black building paper to create a moisture barrier between the concrete and the metal. I will also apply Rust-oleum to the metal. Is there any other way that we can eliminate the metal corrosion in a situation like this in the future?
I am sorry I tried to load a picture of the new hanger but it does not add the photo to the thread. If you know how to load pictures please let me know.

 

[JAE]

Is there any other way that we can eliminate the metal corrosion in a situation like this in the future?

A few things:
1. Not sure about the benefit of Rustoleum if you don't properly prepare the surfaces - sand-blasting or shot blasting (SP-6) would be very helpful for long term durability.
2. There's probably better coating systems than Rustoleum to be honest.
3. Vent the space adequately to minimize humidity.


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[hokie66]

The concrete doesn't cause steel corrosion, but water does. Isolating the steel from the concrete will not solve your problem, and will probably make it worse. You need to find the source of the water and deal with that. Protective coatings help, particularly hot dipped galvanizing.

 

[Agent666]

If the steel is cast into the concrete and its not protected appropriately at the interface it can accelerate corrosion at the location where the steel goes into the concrete.

Noxyde paint system (by rustoleum) doesn't require particularly onerous preparation base don when I've seen it used. Its meant to simply encapsulate any corrosion so removing the worst of it by waterblasting is often enough to get the paint system to bond to the surface. It doesn't need to be blasted back to white metal as far as I'm aware.

 

[m1208]

This is the photo

 

[m1208]

The sketch is the design solution I am recommending. Any thoughts are appreciated.

http://www.eng-tips.com/

 

[m1208]

This is another sketch

 

[m1208]

This is the primer I will use to delay corrosion