Behaviour of FRP wrapped high strength reinforced concrete columns under different loading conditions
FRP has been used in recent years to strengthen concrete members. For FRP wrapped reinforced concrete columns, most of the research reported concerns testing specimens under concentric axial load. In reality the loads on columns can be eccentric due to column’s location (corner and edge columns) or due to construction errors. This paper presents the influence of CFRP on concrete columns’ carrying capacity of concentric and eccentric loads. Twelve high strength reinforced concrete columns were cast and tested. They were divided into three groups: the first (control) group consisted of reinforced concrete columns; the second group consisted of reinforced concrete column specimens wrapped with 3-layers of horizontal CFRP; the third group consisted of reinforced concrete column specimens wrapped with 3-layers horizontal and 3-layers vertical CFRP. From each group, three specimens were tested as columns and axial loads were applied at eccentricities of 0 mm (concentric), 25 mm and 50 mm. The fourth specimen each group was tested as a beam under four-point loading test and load-deflection curves were plotted. Results of this study showed that CFRP is an effective material for strengthening reinforced HSC columns under eccentric loads.