Strengthening of RC beams using prestressed fiber reinforced polymers – A review

• Compared to prestressed steel, prestressed FRPs exhibited good structural properties.
• CFRPs are suitable prestress materials, it covers all the advantages of other FRPs.
• The NSM technique offers a shield to the prestressed material against the environment.
• The 40% prestressing in NSM CFRP rod can give maximum flexural strength of the beam.
• Among different CFRP shapes, CFRP rods are the most effective type under prestressing.

The use of steel and fiber reinforced polymers (FRPs) for strengthening RC beams can significantly improve the flexural strength, fatigue life and the serviceability of the beams compared to un-strengthened beams. Prestressing materials enable the material to become more efficient since a greater portion of its tensile capacity is employed. Investigations have shown that prestressed FRPs are effective materials for strengthening deteriorated structures. This paper presents a comprehensive review on the flexural behavior of strengthened RC beams using prestressed FRPs. The review covers the near surface mounted (NSM), externally bonded reinforcement (EBR) and externally post-tensioned techniques (EPT) and the corresponding advantages and disadvantages are highlighted. Anchorage systems and the effect of prestressing levels on the ductility, deformability and bond behavior of prestressed FRPs are also addressed. Recommendations for the future research are also presented.