New Proposal for Flexural Strengthening of Reinforced Concrete Beams Using CFRP T-Shaped Profiles

Abstract

The purpose of this study was to evaluate the performance of a novel strengthening system using T-shaped carbon fiber reinforced polymer (CFRP) profiles. The proposed system successfully combines the advantages of two established strengthening techniques, namely the near surface mounted (NSM) and externally bonded (EB) methods. The paper presents the experimental results of structural tests carried out on seven flexurally-strengthened and two non-strengthened full-scale reinforced concrete (RC) members. Two T-shaped profiles having heights of 15 and 30 mm were applied. The main parameters of concrete strength and composite strengthening ratio were investigated to evaluate the efficiency of the proposed flexural strengthening system. All specimens were tested under a quasi-static six-point bending configuration. The test results showed a significant increase in the load bearing capacity and the stiffness of the RC beams with strengthening and also a notable reduction in maximum deflections. The high tensile strength utilization of the CFRP profiles places this strengthening technique as a promising alternative to other, less structurally-efficient systems.

Keywords

• flexural strengthening
• CFRP
• T-shaped profiles
• near surface mounted reinforcement
• stiffness
• intermediate crack debonding