Structural Behavior of Hollow Beam Reinforced with Different types of GFRP stirrups

Abstract

The structure could be impacted by concrete's steel reinforcement corroding. When exceptional corrosion resistance capabilities are required, fiber-reinforced polymer (FRP) reinforcements offer a practical choice for constructions exposed to hostile environments. However, only a small number of the building's most important structural components are currently permitted to use FRP bars as interior concrete reinforcement, leaving the rest of the building unprotected. This is due to the lack of available curved or shaped reinforcing FRP pieces, which have subpar structural performance.
 Eighteen concrete beams with dimensions (1200×225×150) mm were divided into three groups and each group had five beams with three References and five different types of stirrups in each group and tested them up to failure. The first group included longitudinal reinforcing steel bars 6Ø10mm, the second group longitudinal reinforcing GFRP bars 6Ø10mm, and the third group longitudinal reinforced with hybrid (3steel+ 3GFRP) bars 6Ø10mm. All beams are self-compacting concrete with a longitudinal hollow with dimensions (50×100) mm.
 The results showed that the ultimate load of a hollow beam reinforced with steel reinforcement is less than a solid beam reinforced with steel (reference 1) by (15%) and a hollow beam reinforcing with GFRP reinforcement is less than a solid beam reinforced with GFRP (reference 2) by (5%), and a hollow beam hybrid reinforced with (Steel+ GFRP) reinforcement is less than a solid beam reinforced with GFRP (reference 3) by (4%).