Axial Compression Behavior of Wall-like Reinforced Concrete Columns Retrofitted Using Different FRP Schemes

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.

Automated summary

Experimental and numerical investigations were conducted on the retrofitting of half-scale wall-like reinforced concrete (RC) columns. The columns were strengthened by using external confinement through fiber-reinforced polymer (FRP) wraps and/or steel/FRP strips with/without modification of the column cross-section. The axial load versus displacement and strain curves were discussed. The experimental results were compared with numerical models, showing a reasonably close agreement with less than 10% error for the peak load. Different confinement schemes led to an enhancement in the load capacity of the strengthened columns in the range of 30-42% compared to the control column. Significant ductility improvements were observed when using FRP wraps after shape modification.