Date of Award
Master of Science (MS)
Ever since Fiber Reinforced Polymers (FRPs) have been used to externally reinforce concrete beams, it has been known that the strength of the bond is what controls the design. Recently, it has been proven that the primary mode of debonding failure is cohesive failure within the concrete substrate close to the FRP/concrete interface. To further enhance the research in this area, finite element analysis has been used to help study this debonding phenomenon.
This thesis is a parametric study of the FRP/concrete interface using finite element analysis software. The finite element model was calibrated using experimental data. The parameters taken into consideration were the geometric configuration of the materials (thickness), the material properties (Young's modulus), the effects of the cohesive zone elements (maximum stress and its corresponding displacement), and finally mixed mode loading conditions.
Conclusions were then made concerning the effects of adjusting the parameters of the model. By increasing the respective thicknesses of the FRP, adhesive, and residual thickness of concrete, the maximum peel load was increased, however, debonding was also faster. In general, increasing Young's modulus of the individual materials had the same effect, increasing the maximum peel load. Mode II loading in the mixed mode loading conditions has a severe impact on the bond behavior, reducing the maximum peel load for initial debonding.