Development and application of innovative triaxially braided ductile FRP fabric for strengthening concrete beams

In this paper, an innovative triaxially braided ductile fiber reinforced polymer (FRP) fabric has been developed for strengthening reinforced concrete beams. The fabric was designed to potentially avoid most of the drawbacks experienced by currently available FRP strengthening systems. The ideal characteristics of a strengthening material for reinforced concrete beams were first investigated. Then, an analytical study was conducted to investigate the undulation effect of diagonal yarns on their loading behavior. Based on these investigations, the fabric was designed, manufactured, and its mechanical properties were experimentally evaluated. The effectiveness of the fabric as a strengthening material for reinforced concrete beams has been investigated by testing four reinforced concrete beams strengthened in flexure and shear using the new fabric. The test results showed that the fabric met its design objectives.