Experimental Study on Confinement Effectiveness of Different CFRP Hybridized Methods in Retrofitting Shear Deficient HSC Columns

The effectiveness of four different carbon fiber reinforced polymer (CFRP) hybridized methods to retrofit the high strength concrete columns with shear capacity deficiency for improving the shear behavior is described in this paper. These retrofitting methods include the wrapped jacketing, the L-shaped jacketing combined with wrapped jacketing, the clamp plates plus wrapped jacketing and the L-shaped jacketing, clamp plates and wrapped jacketing. Five specimens were tested under low reversed cyclic loading. The influence of retrofitting on the failure mode, ductility, strength, stiffness degradation, and distribution of CFRP strain is analyzed. The results indicate that the retrofitted specimens exhibit high levels of ductility superior to the reference specimen. Among the four retrofitting methods, the effectiveness of method of only the wrapped jacketing is the worst, the method of the clamp plates plus wrapped jacketing has better performance compared to the method of the L-shaped jacketing combined with wrapped jacketing, and the method of the L-shaped jacketing, clamp plates and wrapped jacketing performs best.