Introduction This study uses nonlinear finite element analysis (NLFEA) to explore the shear response of externally strengthened reinforced concrete (RC) beams with carbon fiber reinforced polymer (CFRP) composite materials. Methods Three finite element models (FEM) were developed and validated against experimental results published in the literature. Results The results revealed an accurate simulation for the shear behavior and captured the enhanced efficacy of externally RC beams utilizing CFRP laminates/sheets under three-point loading. A 3D NLFEA with perfect bonding is alongside Lu et al.’s bilinear cohesive zone material (CZM) model/bond-slip law (local bond shear stress-slip model) employed to simulate the shear response of CFRP externally strengthened RC beams. Furthermore, the verified model was employed in a parametric investigation examining the impact of concrete compressive strengths on the ultimate load, load-midspan deflection responses, stiffness, absorbed energy, and failure pattern of strengthened RC beam specimens. It was concluded that increasing the concrete compressive strength from 60 to 150MPa enhanced the load capacity, ductility, and total absorbed energy of the RC beam specimens from 56 to 101.52%, 2.39 to 20.00%, and 77.60 to 166.61%, respectively.
Sadoun et al. (2026) studied this question.