Slab on Grade at Interior Columns
Slab on Grade at Interior Columns
(OP)
I am curious to here from others on how they usually detail this. I have seen it both ways but more often the top option rather than the bottom. It seems that the bottom row of details would be more work. We have a project where the geotech is (sorta) recommending the bottom row of details so that the slab does not bear on the footing or pier. I am wondering though if the top of footing is a -1'-0" how much does the granular subbase really compress, why not just pour on top of the footing?
Thanks.
Thanks.






RE: Slab on Grade at Interior Columns
Yes, isolate the slab from the top of footing.
The bottom plan detail results in offset joints that will crack in odd places.
RE: Slab on Grade at Interior Columns
RE: Slab on Grade at Interior Columns
RE: Slab on Grade at Interior Columns
For the other two details, I have used the constant slab thickness shown in the lower details. Why do you think the bottom details would be more work? I would think the opposite.
Where there is a large gap between the top of footing and underside of slab, there could be a concern about adequately compacting the region around the pier, so backfill would have to be done carefully. Granular backfill or low strength concrete (Fillcrete) might be an option.
BA
RE: Slab on Grade at Interior Columns
RE: Slab on Grade at Interior Columns
At interior columns - do you size the diamond so that it covers the base plate?
At exterior columns - do you keep the same size as the pier? If yes how do you detail the control joint?'
Thanks again!
EIT
www.HowToEngineer.com
RE: Slab on Grade at Interior Columns
the exterior ones i typically use the same size as interior.
Honestly they are standard details which go on every set of plans my firm make that involve steel columns. I check but really don't think much about.
RE: Slab on Grade at Interior Columns