Anomoly 1: Strange Column Bondage

On the first and second floor, there are 2 pairs of mated columns with sub-beams and capitols.

Behind the post in the foreground, there are two mated columns, whose function I do not know of.

you can see one of them here, in this photo  of a second floor apartment

on the right of the photo, here the same ones from the first floor, at a different angle. Other posts appear to be the Y arm variety.

bonded columns for what?