Strength of reinforced concrete columns bonded with external steel plates

Rehabilitating reinforced concrete elements using external steel plates has been applied to both beams and slabs in bridge and building construction over the last two decades. The effect of applying external steel plates increases the strength of beams and slabs. This technique can also be applied to reinforced concrete columns to increase their strength with a minimal increase in the cross-sectional dimensions of the member. This article presents an experimental programme used to ascertain the behaviour of both short and slender columns. These columns had steel plates bonded to them by the use of both bolting or gluing and bolting. A simplified theoretical model based on composite construction techniques is then presented and calibrated with the experiments to determine the strength increase and recommendations for further research are then made.