We had someone remodel our deck using some of the existing wood and posts. He replaced some of the post but the problem is he replaced post on a concrete patio and used no post brackets or anchors, is their anyway to put anchors or brackets around the post after the deck is up. Is it possible to add another post beside it with an anchor.
Cut half of the post on one side and chisel/punch it out so that the post is only bearing on half of it's cross section. The get a piece (say 1' long) of angle iron (3x3) and lag it into the side that you just cut. The angle will act as a temp support while you cut the balance of the post.
Another possibility is to drill a 1-1/16 hole through the post about 1' up from the bottom. Insert a steel rod and use jacks on wither side to hold the post up while you cut the bottom off.
In either case, you need to size the angle, lags, and rod for the load on the post.