deep grout beds under steel columns
deep grout beds under steel columns
(OP)
I've got a couple columns located within a slab depression, and the revised base plate elevation didn't get picked up on shops... which leaves about 7" between bottom of base plate and top of bearing surface. Column loads are on the order of 400-450k, shear/moment are not concerns at this location (other than incidentals during erection), and anchor bolts have sufficient length to be set high.
Refabricating the steel would cause significant delays, and forming/reinforcing a 5" long pedestal seems a bit much. Other than putting some pea gravel in the grout mix, are there other significant problems with just simply grouting this space solid, maintaining 45 degrees out from the base plate?
Refabricating the steel would cause significant delays, and forming/reinforcing a 5" long pedestal seems a bit much. Other than putting some pea gravel in the grout mix, are there other significant problems with just simply grouting this space solid, maintaining 45 degrees out from the base plate?






RE: deep grout beds under steel columns
Can you have to contractor place additional base plates so that you can get the required grout thickness down? I wouldn't think they would need to be welded for gravity loads and would be more like full-size shims.
RE: deep grout beds under steel columns
So how on earth are you going to deal with the anchor rods?
RE: deep grout beds under steel columns
Adding additional thickness of plate should work, and the fabrication should be pretty quick on those... we've got about 3 weeks until the first steel goes up, so that should be more than enough time to get a few more plates done. A quick call to the grout manufacturer sounds like a good idea as well, even if the base mix won't do this, it stands to reason they might have another mix that would. Thanks for the quick response!
RE: deep grout beds under steel columns
RE: deep grout beds under steel columns
I don't think it is too much, and it is the contractor's mistake isn't it?
A single tie around the anchor bolts, formwork and you're ready to pour. Easier than packing in 7" of grout I would think.
RE: deep grout beds under steel columns
RE: deep grout beds under steel columns
Dik
RE: deep grout beds under steel columns
I believe he said in the OP that this was a gravity only column (or at least that shears and moments were not a concern at this location).
RE: deep grout beds under steel columns
RE: deep grout beds under steel columns
Keep in mind, JMorrison, that there never seems to be enough time to do it correctly, but always enough time to do it over!
Rod