cold joints in retaining wall heel slab

[longhornse]

Question:
I have another concrete cold joint problem. This one is on the cantilever retaining wall heel slab. The base slab is design for 24" thick. Cold joint is at 10" from ground. My gut feeling is we need to do something. Can somebody tell me what are the remediations other than saw-cutting and replacing it? What about pressure-injetting epoxy to fill up the voids at the cold joint? Please advise. Many thanks.

 

[Roadbridge]

Have you taken any core samples and tested them to see if they fail along the cold joint plane?

 

[longhornse]

As a matter of fact, we did try to take a core sample but it broke at halfway.

 

[Roadbridge]

Longhornse

Have you done an ultra sound test to determine the extent of the voids with in the heel?

 

[longhornse]

Roadbridge,

No, we haven't. I don't think we have any intention of doing that. Do you think it will help? When the core broke halfway, I was almost certain that it was due to the cold joint. An ultra sound test may not be able to tell me a lot. It would if there is honeycombing in the slab. Please correct me if I am wrong. Thanks.

 

[miecz]

Sounds like you have a 14 inch thick footing on a 10 inch levelling pad. Perhaps you can dowel the two together.

 

[keano1]

Have you rechecked the design assuming it to be just 10' thick heel.
Injecting epoxy, can you be sure it will work?

 

[Roadbridge]

This cold joint dose it run the entire lenght of the footing or is localised in one area.

Keano1 may have hit on some thing at looking at the design again, but see how the 14' section reacts in the design rather than the 10'.