Abstract
This study investigates the effects of graphene oxide (GO) incorporation on the flexural behaviour of lightly reinforced concrete beams. Six beams were fabricated with varying GO concentrations (0%, 0.01%, and 0.05%) and concrete strengths, then tested under monotonic loading. Results demonstrated that GO addition significantly enhanced both mechanical and structural properties, with more pronounced effects in lower-strength concrete. Compressive strength improvements reached 17% and 45% for high and low-strength concrete respectively, whilst ultimate load capacity increased by 17.19% and 45.24%. GO incorporation resulted in up to 40% reduction in crack widths and improved ductility, particularly in lower-strength specimens. However, high-strength beams with 0.05% GO exhibited premature reinforcement rupture, indicating the need for balanced design considerations. The optimal GO content was consistently 0.05% by weight of cement. These findings suggest GO modification is particularly beneficial for enhancing conventional concrete structures, though strength-specific design modifications may be necessary for high-strength applications.