Design for shear strength of concrete beams longitudinally reinforced with GFRP bars

• Published in: Structural engineering and mechanics Vol. 53; no. 1; pp. 41 - 55
• Main Authors: Thomas, Job, Ramadass, S
• Format: Journal Article
• Language: English
• Published: 10-01-2015
• Subjects: Beams (structural); Compressive strength; Fiber reinforced plastics; Glass fiber reinforced plastics; Mathematical models; Reinforcement; Shear; Shear strength
• ISSN: 1225-4568; 1598-6217
• DOI: 10.12989/sem.2014.53.1.041

In this paper, a model for the evaluation of shear strength of fibre reinforced polymer (FRP)-reinforced concrete beams is given. The survey of literature indicates that the FRP reinforced beams tested with shear span to depth ratio less than or equal to 1.0 is limited. In this study, eight concrete beams reinforced with GFRP rebars without stirrups are cast and tested over shear span to depth ratio of 0.5 and 1.75. The concrete compressive strength is varied from 40.6 to 65.3 MPa. The longitudinal reinforcement ratio is varied from 1.16 to 1.75. The experimental shear strength and load-deflection response of the beams are determined and reported in this paper. A model is proposed for the prediction of shear strength of beams reinforced with FRP bars. The proposed model accounts for compressive strength of concrete, modulus of FRP rebar, longitudinal reinforcement ratio, shear span to depth ratio and size effect of beams. The shear strength of FRP reinforced concrete beams predicted using the proposed model is found to be in better agreement with the corresponding test data when compared with the shear strength predicted using the eleven models published in the literature. Design example of FRP reinforced concrete beam is also given in the appendix.