Ductility of biaxially loaded high strength reinforced concrete columns

Eight reinforced High Strength Concrete "HSC" columns of dimensions 150 × 150 × 1200 mm were cast, tested and studied for both strength and deformational behavior. The investigated parameters included ratio of load eccentricity in both x and y directions, the reinforcement ratio and configuration, and vertical steel percentage. Within the limits of the test results of this study, it was found that increasing load eccentricity resulted in reducing the ultimate capacity of the studied HSC columns by approximately 15%. In addition, increasing the lateral confinement lead to an increase of ultimate capacity by approximately 22%. Moreover, the configuration was more effective than ties reinforcement ratio on the ductility of studied HSC columns. Increasing vertical steel percentage lead to an improvement of ductility of HSC columns. A proposed design formula was developed for predicting the capacity of eccentric and biaxially loaded HSC columns