Quick Question: Ram Foundation Soil Bearing Capacity

I am wondering what the difference is between the "Max Unfactored Soil Bearing" and the "Max Average Unfactored Soil Bearing". I have referred to the technical notes for the analysis of spread footings and I was able to replicate the "Max Unfactored Soil Bearing" value for both my gravity and lateral members in my model, and this was perfect. Yet, I am now trying to look at the soil bearing for a unique case...I have a group of 3 columns sharing one large spread footing. The way I modeled it is accurate to what is currently constructed (this is an analysis for expansion of an existing building). I have a continuous footing beneath two lateral columns, and a spread footing under the one gravity column (this column has eccentricity), and these two foundations overlap. I was able to replicate the values for the continuous footing, but surprisingly not the spread. Or I did...but rather than obtaining the "Max Unfactored Soil Bearing" like I was for all other foundations, my calculations produced the same value for the "Max Average Unfactored Soil Bearing"

Something that may be affecting this, but I am unable to determine how, is that the gravity column atop the spread footing is technically designated as "lateral", but all the connections are pinned since I want it to act as gravity. My forces do not show any moments going into my foundations, which is what I want. The reason for designating it this way is to create a load path for the braced penthouse framing on the roof of the building.

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