Corrosion of Reinforcement in Construction Joint 1

[bdbd]

What is keeping the reinforcement in construction joint from corroding? Even if we use waterstops, it's in-between the outer and inner reinforcement, leaving outer reinforcement exposed to the water and other corroding agents in the joint area.

 

[WesternJeb]

Correct. In extreme situations you could use epoxy coated rebar on the outside face... Most of the time I have justified your point by assuming that corrosion is localized to just a few pieces of reinforcement and the load spreads out everywhere else via transverse reinforcement.

 

[TLHS]

Depends on what the construction joint is. The concrete itself provides some amount of chemical protection from corrosion. A reasonably tight construction joint will also provide some amount of protection from direct contact with water.

That being said, if I'm in an outdoor service and it's critical I'll do things like block out the top of the construction joint and have them seal the crack.

 

[BridgeSmith]

For a construction joint that gets inundated with water on a regular basis, or with salt water occasionally, I would recommend using epoxy coated rebar and an epoxy resin bonding compound in the joint.

 

[dik]

or preferably HDG.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[Smoulder]

CJ is basically a very fine crack. So no worse than any other crack if you're talking beams and slabs. Could be worse in non flexural element but still better than beams and slabs because no tension to open it more.

 

[BridgeSmith]

I agree with Smoulder that from a corrosion perspective a const. joint is similar to any other crack. As long as the alkaline Ph of the concrete remains, it will inhibit corrosion as well at the CJ as anywhere else in the beam/slab/wall.