What is the purpose of concrete capitals below teleposts in basement

[CANeng11]

I'm being asked if the concrete capitals below the teleposts shown in the picture attached can be removed. What is the purpose of these? I have no information on the footing below. The house is from the 50's or 60's.

 

[jayrod12]

Depends whether there is a dedicated footing below or not. If yes, then I don't necessarily see an issue with cutting it down. If no, then I'd bet it's intended to spread the load further before the slab.

 

[Brad805]

That looks like an afterthought and there may not be a footing below.

 

[JoshPlumSE]

My guess is it's there for punching shear in the slab.

 

[skeletron]

Less chance of someone bashing into the bottom during downstairs roller hockey games and the whole thing coming down. But yeah, probably to make a "footing" where there wasn't one.

 

[jayrod12]

It is common in my area for there to be pedestals even with a dedicated footing below. But when that is the case, you can usually clearly see that the slab is separate from the pedestal. It does not appear that way in this picture.

 

[3DDave]

Something is going on with that floor - the furnace is sitting in a shallow portion as if they poured a half-inch (1 cm) of leveling material.

 

[r13]

Supports in the basement are typically raised above the floor to avoid accidental water damages. Looks like the original pad for the furnace was removed for height adjustment. I think in this case, there is no flood concern, so lower the post should be fine, provides the base plate should be as large as the existing foot print.

 

[dik]

Maybe so you know where the centre of the footing is when the slab is poured.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?
-Dik

 

[WARose]

I don't know that I would call that a "capital". Looks like someone just trying to make up for a elevation mix up with a tall grout pad. (Or, going with r13's idea, protecting for flood.)

Likely there is no rebar in it (like a capital).

 

[r13]

It is a pedestal. Same concept as setting outdoor wood post above ground. Capital is located on top of the column, below slab/drop panel.

 

[BAretired]

Based on your current knowledge of the foundation, removal of the truncated pyramid cannot be recommended.

BA

 

[BridgeSmith]

I concur with BAretired; it may be necessary to spread the post loading over a sufficient area of the slab, so that the post doesn't punch through. Without knowing what the loads are and the thickness of slab, it would unwise to remove it, unless a sufficiently thick base plate of at least the same size replaces it.

Rod Smith, P.E., The artist formerly known as HotRod10