Beam-column joints in reinforced concrete frames built before the 1970s were designed for gravity loads only and do not meet current design code requirements for seismic resistance. Therefore, these joints fail prematurely and exhibit non-ductile behaviour. In this study a 3D nonlinear finite element model is developed for the analysis of beam-column joints strengthened with externally-bonded steel-reinforced polymer (SRP) sheets. Three different wrapping configurations are used. The joint model is analyzed under cyclic loading applied at the beam tip to simulate high levels of inelastic deformations similar to those experienced in severe earthquakes. Concrete is modelled based on combination of constitutive models for cracking and plasticity. The model is verified by comparing the results with those obtained from experiments. A reasonable agreement is obtained between the experimental and the numerical results. The model can be used to study the effects of parameters such as the amount and orientation (the ply angle) of the SRP reinforcement, the concrete strength, the level of axial load on the column, and the geometry of the joint.
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