Abstract Strengthening of reinforced concrete (RC) beams has been an important focus due to deterioration, strength degradation, code compliance, change of use, and increased loading demands over time. This study investigates the flexural enhancement of RC beams using external steel elements with various end conditions. Nine beams were tested under three points loading: three control and six strengthened specimens. Strengthened beams were grouped into two categories. In the first, external rebars were attached only in the maximum flexural zone; in the second, they were extended to the full beam length. To prevent delamination, external bars were anchored with 90° hooks and fixed by welding and epoxy. Results showed that strengthened beams achieved higher ultimate capacities compared to control beams. Beams strengthened only in the maximum moment region exhibited a 21.5 % increase in flexural strength, while those reinforced along the entire span reached a 92.6 % increase. The findings confirm that extending external steel reinforcement throughout the beam length provides a significant improvement in flexural capacity and can be adopted as an effective strengthening technique for RC structures.
Khan et al. (Thu,) studied this question.