Deep beams generally suffer from limited shear capacity and ductility due to their specific aspect ratio and the significant contribution of shear deformation to their overall response. Consequently, various methods have been employed to strengthen these structural members. Among these, reinforcing the beam web with Carbon Fiber Reinforced Polymer (CFRP) sheets is considered one of the most effective solutions. Given the inherent limitations of conventional steel reinforcement in significantly enhancing shear capacity and ultimate strength, CFRP sheets have emerged as an effective alternative and are currently the focus of extensive research. In this study, the shear behavior of CFRP-strengthened deep beams is investigated using numerical simulation in the ABAQUS finite element software. To this end, sixteen deep beam specimens with constant longitudinal reinforcement but varying shear span-to-depth ratios (a/d) were designed and analyzed under two concentrated loads equidistant from the supports. From this set, four models served as control specimens (un-strengthened), and the remaining twelve models were strengthened in the shear zone using CFRP sheets. The results indicated that the maximum shear contribution of CFRP is achieved with a 135 degree orientation, particularly in beams exhibiting shear-dominant behavior (low a/d ratio). Specifically, an increase in ultimate capacity up to 50% was observed, along with a reduction in rebar stress compared to the strengthened state.
