Shear performance of short-span FRP-reinforced concrete beams strengthened with CFRP and TRC

Abstract

This paper presents an experimental program to study the shear performance of short-span GFRP (glass fiber reinforced polymer) bar-reinforced concrete beams strengthened in shear with CFRP (carbon fiber reinforced polymer) laminates or TRC (textile reinforced concrete). Seven short-span concrete beams reinforced with GFRP bars, which have an aspect ratio of 1.7, are strengthened in shear with various schemes. Two un-strengthened beams, which have limited and no transverse reinforcements, are used as the controlled specimens. Two commonly used strengthening methods, namely CFRP strip and TRC are applied to the tested specimens. The number of textile layers is investigated in this experimental program. The U-wrapping strengthening configuration is used for both CFRP and TRC methods. The experimental results indicate that both TRC and CFRP schemes effectively enhance the shear strengths of short-span FRP-reinforced concrete beams. The number of textile layers slightly affects the shear strengths of the tested beams because the failure is controlled by the crushing of the concrete struts in short-span beams. A simple strut-and-tie method is used in the last part of the paper to predict the shear strengths of the tested specimens.