Effect of Confinement on the Axial Performance of Fibre Reinforced Polymer Wrapped RC Column

The combined effect of internal steel ties and external FRP wrap was investigated using nine reinforced concrete columns with varying thickness of external wrap. The load, deflection and lateral expansions were studied at yield state and ultimate state. The results from the experimental investigations were used for performing a multi-variate linear regression analysis incorporating the contribution of tie spacing as a term. The predictions of the regression equation agreed well with the experimental results and showed sensitive difference in compressive strength for changes in tie spacing.