Experimental and numerical investigations on the retrofitting of half-scale wall-like reinforced concrete (RC) columns were conducted. The axial compressive behavior of the control un-strengthened wall-like RC column (having a section aspect ratio of four) was compared with the strengthened columns. The columns were strengthened by employing external confinement through fiber-reinforced polymer (FRP) wraps and/or steel/FRP strips with/without modification of the column cross-section. The characteristics of axial load versus displacement and strain curves were discussed. The experimental results were also compared with the numerical models, which were first validated against the previous studies. A reasonably close agreement was achieved between the numerical and the test results with an error in prediction of less than 10% for the peak load. With the different schemes used for confinement, the enhancement in the load capacity of strengthened columns was in the range of 30–42% of the control column. In addition, significant ductility improvements were seen in schemes that employed the FRP wraps after shape modification.

The fracture characteristics of a simple reinforced concrete beam retrofitted with an FRP laminate are difficult to predict due to its composite nature. Lagrangian mechanics involved in the large deformation further complicate the analysis and computation when the retrofitted beam is subjected to quasi-static loadings. In the present study, finite element approach has been used to analyse the behaviour of a RC beam that has been retrofitted with FRP laminates under a range of quasi-static loadings. The Concrete Damaged Plasticity (CDP) material model was used for nonlinear finite element modeling of the concrete material in ABAQUS/Explicit module. The rebar was embedded in the concrete using constraint elements. Damage parameters for the FRP were used using the Hashin criteria. The experimental studies were used to validate the numerical model that was thus developed, and a good correlation was found. Due to high yield tensile strength of FRP laminates, the retrofitted reinforced concrete beam’s crack initiation was significantly postponed. At the edges of the beam, FRP debonding was particularly evident.