Influence of concrete strength and prestress level on the shear behavior of prestressed concrete beams

This paper investigates the influence of concrete strength on the shear behavior of prestressed high-strength concrete beams. A validated three-dimensional nonlinear finite element model was developed on ABAQUS software to conduct a comprehensive parametric investigation. The tested parameters encompassed normal and high strength fully and partially prestressed beams designed for shear failure. The numerical results show that increasing concrete strength leads to a systematic enhancement of shear resistance, accompanied by a reduction in the normalized shear index. A comparative assessment with the provisions of ACI 318-25 [1] reveals that the associated safety margins are dependent on concrete strength rather than prestressing level. These findings highlight the need for focused strength-dependent considerations in shear design formulations for prestressed high-strength concrete structures.