I'm not familiar with "Loxins" but a quick search of the
Loxins & Dynabolts are often mentioned together. I can only assume the
Loxin is a sleeve style anchor that yields in internal thread so the
mating bolt can be repeatedly installed & removed.
The problem with sleeve style mechanical anchors is that they apply a
certain amount of splitting for the to material into which thye are
installed. Dynabolts should not be placed with 75mm of the edge of
concrete. Brick is usually much weaker.
I would use a chemical anchoring material & install coupling nuts to
create the internal subflush thread. Chemical anchors do not apply
splitting force. You might get the bricks alone to work. What's
below the brick?
I guess you could pour the thicker concrete base, epoxy the nuts into
the concrete, cover the concrete w/ bricks (for appearance). drill
clearance holes through the brick & attach bollards as before.