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ford347
2011-02-24, 08:17 PM
I am having some issues with round, isolated footings, my HSS structural columns and my concrete pedestals and their attachments.

I have a sloping 4" structural concrete slab in place. I have placed HSS 5x5 columns on grids and have attached them to the structural concrete slab at their base with a 3/4" offset for a base plate. We will be mounting these columns directly to the top of the structural slab. I've then placed 24" x 6' deep caisson footings below these columns. The midpoint of the top of that footing intersects the bottom of the actual slab and I have joined their geometry. I got to that point with no real issues. There then needs to be 16" round, concrete pedestals poured on top of the slab around the column and project 30" above the slab.

My problem is, no matter if I use a isolated footing or a concrete structural column, when I place the pedestals at the HSS column locations, it automatically moves the footing to the base of the column. If I use the isolated concrete footing, it moves them to the bottom of the HSS 5x5. If I use the concrete column for the pedestal, it attaches them and moves them to the 24" isolated concrete caisson footings. In either case, Revit does not give you the option to detach the footing(s) from either column, so I can't get the pedestal on top of the slab and surrounding the HSS as they need to be.

Should I be using something different for the pedestal or have I done something in the wrong order? In this case, the structural slab is really the host of the HSS and the 16" concrete pedestal. The 24" caisson below is poured and a part of the concrete slab.

Thanks,
Josh

Craig_L
2011-02-24, 11:56 PM
In revit structure (2011) I have the option to detach the column at the top/base.
Also, if this doesnt work, ask the question, is you column attaching to slab, or the footing?
If the column is actually being plated onto the footing then you just need to set your column <slab depth> below your level and then your footing will place in the correct spot. If the column is not attached to the footing, but plates onto the slab, then your footing is a pier/pile and you should use that family rather than a footing family and that will also solve your problem.