Strengthening of RC Beams using Externally bonded GFRP sheet

Abstract

Fiber-reinforced polymer (FRP) materials are used in di erent con gration and techniques for strengthening of Reinforced concrete (RC) elements to ensure their longer service life. Use of FRP material as Externally bonded surface is one of the popular strengthening techniques that consists of bondinf FRP material using primer and saturant. An attempt has been made to investigate the structural performance of simply supported RC beams strengthened with Externally bonded GFRP sheet. Flexural and shear strengthening of RC beams is conducted using GFRP sheet. Total 22 beam specimens are cast and subsequently are strengthened using GFRP sheet. 10 beams are strengthened in exure and 12 beams are strengthened in shear.Size of beam is kept 150mm 200mm 2100mm. Beams are designed using IS provisions. The beams are made de cient for exure and shear by reducing percentage of tensile re- inforcement and required shear reinforcement, respectively. Analysis of strengthened beams is conducted using ACI provisions. Variables considered in exure strength- ening of beams are change in number of sheet layer , ber orientation angle and area of FRP material.Variables for shear strengthening of beams include change in num- ber of layers, ber orientation angle and depth of GFRP sheet. The RC beams are subjected to two point loading during testing.FRP strengthened beams de cient in

exure exhibited increment in exure load ranging from 15.5% to 43.5% as compared to that of control beam. Shear strengthened beams have exhibited 19.12% to 69.12% increase in load as compared to that for control beams.