Why the fiber reinforcement has not replaced the steel bars so far? At least it can be used in the basements that are likely be submerged in under ground water. No crack width eavaluation whatsoever in that case! I think it is much cheaper than steel bars in this case. So if sulfates, clorides, etc are attacking the piles, raft, retaining walls the crack with should be 0.3mm and in some cases 0.2mm and even 0.1mm! That's except the water proofing, water stops and the time spent for all these activities.
I think we have to overlook at all these parameters involved in the selection of rebars.