Repair for core through rebar

[canwesteng]

A contractor has cored through bar in a concrete beam. I've come up with an idea that works, but I'm wondering if there's something obvious that I'm missing that might make it easier. My plan is to chip out concrete, and use mechanical couplers and a small section of new bar to splice the bars together. Then patch when it's all said and done. My sketch is attached.

 

[TehMightyEngineer]

That's the repair I would recommend and is likely the easiest and most viable.

Professional and Structural Engineer (ME, NH, MA)
American Concrete Industries

http://www.americanconcrete.com

 

[canwesteng]

I should add, it's old rebar (circa the 1960s), called out as 20 ksi billet steel. In my mind that says nothing about weldability, and take some material for testing to determine if we can weld to it isn't an option.

 

[TehMightyEngineer]

I'd avoid welding bars already embedded in concrete if at all possible, regardless of whether they're weldable or not.

Professional and Structural Engineer (ME, NH, MA)
American Concrete Industries

http://www.americanconcrete.com

 

[msquared48]

Does the beam have to be spliced? Is there enough capacity in the remaining steel to do the job?

Look at the maximum moment the beam sees at the point of the cut and design for that moment. See if the remaining bars can handle it.

Mike McCann, PE, SE (WA)

 

[canwesteng]

I've come up with a solution like that as well. Based on the drawings, there should not have been bar where the contractor cored, so the issue is identifying what's actually left in the beam. And then the issue is convincing the client that taking out excess bar hasn't weakened the beam at all.

 

[sandman21]

The wedge will only line up with one existing bar and would engage the new and the one old bar, the wedge wont be engaging the other existing bar. I would make sure that the coupler is good for your situation. You can take the piece of rebar in the core and have a chemical test to get the CE, carbon equivalent, to determine the required pre-heat, etc.