Behavior of reinforced concrete columns confined with CFRP (Carbon fibre reinforced polymer)

Abstract

In modern world the retrofitting of structures is promoted rather than demolishing and reconstruction of deteriorated structures.Attentionhas also given to increase the load carrying capacity of existing structures to increase the usage capacity or to change the intended usage. Retrofitting of structures using Carbon Fibre Reinforced Polymer materials is accepted as a sustainable and effective method comparatively to most of other well-known methods like steel plate bonding and external post tensioning. This paper presents anexperimental study carried out to understand the effectiveness of external CFRP confinement for square reinforced concrete columns and validation of ananalytical stress strain model,using experimental results. Four reinforced concrete columns, one control specimen without external confinement and three specimens with full external confinement were tested for compression to monitor the strength gain against axial loading. The results showed a considerable increase of the axial strength, about 50% and improved ductility, up to about 20% for the columns with external confinement. The analyticalstress stain modelpresented anacceptable agreement with obtained experimental results.