Effect of Fiber Orientation on Shear Behavior of RC Beams Externally Strengthened with CFRP

摘要

Strengthening of reinforced concrete beams with carbon fiber reinforced polymer (CFRP) is one of the recent applied strengthening techniques. It offers an attractive solution to enhance shear and flexural capacities of reinforced concrete (RC) beams. Behavior in shear and flexure of reinforced concrete beams externally strengthened with CFRP is highly influenced by the way in which these composites are bonded to the beam. In this paper reinforced concrete (RC) beams strengthened with CFRP was modelled using a nonlinear finite element (FE) model to study the influence of the orientation layer of CFRP on the overall response of strengthened RC beams in shear. This is carried out to achieve the optimum utilization of such strengthening technique in terms of load bearing capacity and possible deflection values. A nonlinear finite element software ANSYS was utilized in this study. The analysis of the results indicated that the overall behavior of the FE models have a good agreement with corresponding previous experimental results. Further, the parametric study proved that shear strengthening of RC beams with vertical CFRP fabric is more efficient than strengthening with CFRP fabric inclined at an angle of 45°. Furthermore, strengthening the reinforced concrete beams with one layer of U-wrap CFRP fabric inclined at an angle of 45° with an additional horizontal layer of CFRP fabric on both sides of the web is more efficient than strengthening with one layer of U-wrap vertical CFRP fabric with an additional horizontal layer of CFRP fabric on both sides of the web.