When I put up my 4 post lift, I had to anchor the posts. It was messy
and time consuming, but what I did was; bought high quality 5/8"
expanding anchors, drilled with a hammer drill and a new concrete bit &
epoxy-ed them in. I started out with Hilti epoxy, but ran out. The
Hilti store is ~ 35 miles so I tried Home Depot. They have a 2 part
epoxy in a caulking gun tube, that if I were to do it again I would use
from the get go. Those last 4 holes were the easiest and the best. None
of the anchors ever came loose, and I regularly raise 6000 lb pick-ups
and shake them around working on them. I sold my Hilti epoxy gun after
finding these glue tubes, highly recommended.
Just an after thought, what about sinking threaded inserts into the
concrete when it is poured? You could have bolts in them to keep the
concrete out of the threads, and remove them after it cured to solve
the tripping hazard.