Column Base Grouting

[StructuralEd]

Is there any method or material appropriate for restablishing bearing under column baseplates that have a slight gap under them due to either unlevel leving plates or tilted column bases that resulted after leveling up the erected steelwork?
I am referring to tapered gaps in the 1/8" to 1/4" dimension.
An initial search seems to indicate that grouts need to be 1" or greater in thickness.

 

[structSU10]

AISC 360-05 M4.4 says if gaps exceed 1/16" but is less than 1/4", and engineering investigation shows that sufficient contact doesnt exist, nontapered steel shims can be used.

 

[StructuralEd]

I agree that contact is not appropriate.
Non-tapered shims would only make very small contact and would basically mirror the condition at the other edge having contact.

 

[structSU10]

I'm just quoting AISC standard.

And I think the statement is saying that if the reduced bearing area is sufficient to carry the load, you don't need to do anything, but if you need something, it says add non-tapered shims. They get this from testing they did, per the commentary.

 

[racookpe1978]

I think we all agree a "perfectly tapered" taper shim would solve the problem "perfectly" - except "that ain't gonna happen" in the real world.

Is the reason for the generic 1" to 2" grout the realization that a very thin, tapered 1/8 or 1/4" grout filler simply can't be injected under a baseplate sufficiently even enough to ensure enough face-to-face contact on both top (grout-to-baseplate surface) and bottom (grout-to-concrete surface) of the grout?

 

[hokie66]

This is the drawback to using leveling plates. They aren't always level or perpendicular to the columns. Sometimes, the leveling plates have to be removed.