Effect of transverse steel on the performance of RC T-beams strengthened in shear zone with GFRP sheet

The focus of the present paper is on the study of the effect of transverse steel on the performance against shear and modes of failure of simply supported reinforced concrete (RC) T-beams strengthened in shear zone with glass fiber reinforced polymer (GFRP) sheet. Eighteen RC T-beams of 2.5 m span with and without transverse steel reinforcement are cast at the structural laboratory of IIT Kharagpur. Nine beams are used as control beam specimens in three different stirrups spacing such as without stirrups and with stirrups at 200 mm and 300 mm spacing and rest nine beams are strengthened in shear zone with GFRP sheet in U-jacket, side bonded and U-jacket with anchorage in each type of stirrups spacing. All the beams are tested in 300 Ton Universal Testing Machine (UTM). The test result clearly demonstrates the GFRP sheet in U-jacket with anchorage is much more effective than the U-jacket scheme.

► The gain in shear capacity is significant in all the GFRP strengthened RC T-beams.
► The transverse steel is more strained in control beams as compared with strengthened beams.
► The anchorage of GFRP sheet eased the strain in longitudinal steel reinforcement.
► The RC T-beams, becomes more flexible and more deformable, after strengthened with GFRP sheets.
► The combination of GFRP sheet with transverse steel shows the failure is due to GFRP rupture.