Dear Ramkrishna,
it is not clear from your question if you have already read section "2.1.8 How to model carbon or glass fibre wrap (CFRP, GFRP) strengthening in ATENA?" of the ATENA Troubleshooting Manual? In short, if you do not like to check debonding manually in postprocessing, you basically have 2 options:
A. modelling the strengthening with dicrete reinforcement bars and defining a bond slip-strength law. Can only capture slip along bar direction.
B. using Interface (GAP) material between the wrap and the concrete. Can capture delamination, but please mind the additional costs both in model preparation (determining interface material properties, etc.) and during the analysis (additional calculations and possible numerical problems).