I installed a bolt in the floor of the garage to lock my mountain bike to. (the apartment people can suck it).
Basically, use a closed-eye bolt of at least 3/8" diameter (10mm) steel. Drill a hole in the concrete not much bigger. Blow out the dust with compressed air (use eye protection), then prepare a gap filler adhesive such as JB Weld. Cement in the eye bolt and wait 48 hours for the glue to set.
Chip H.