High strength concrete columns reinforced with high strength steel

This paper presents an experimental study of the behaviour of four high strength concrete (HSC) columns confined by helical reinforcement of 500 MPa and with 500 MPa longitudinal reinforcement. Two normal strength concrete (NSC) columns confined with a 500 MPa-grade helix and two confined with, a 250-grade helix with 400-grade longitudinal bars were also tested. The helices were made of size 10 mm diameter bars and had a constant helical diameter of 160 mm. The effects of the distribution of the longitudinal bars and the pitch sizes for the helical reinforcement are compared using 50 mm and 75 mm pitches. With this variation in design, a higher strength, yet more ductile column can be achieved.