Behaviour of FRP wrapped square reinforced concrete columns under eccentric loading
The majority of studies dealing with FRP strengthened columns deal with columns of a circular cross section. Moreover, most concrete columns in the field have square or rectangular cross sections and resist eccentric loads as well. In this paper, the influence of two parameters that are the number of FRP layers and the magnitude of eccentricity were studied experimentally. A total of sixteen short square reinforced concrete columns wrapped with carbon FRP (CFRP) composites were investigated in this study. The columns had the dimensions of 200 mm x 200 mm x 800 mm and a round corner with a radius of 34 mm. Twelve columns were tested under compressive loading and four columns were tested under flexural loading. Based on the number of CFRP layer, the columns were grouped into four: unwrapped, wrapped with one layer, wrapped with three layers, and wrapped with two layers after the application of one layer vertical CFRP strap. From each group, one column was tested under concentric loading, one column was tested under 25 mm eccentric loading, one column was tested under 50 mm eccentric loading and the last specimen was tested under flexural loading. The results showed that wrapping a column with CFRP composite increases the load-carrying capacity and ductility of the column.