Degree Name

Doctor of Philosophy


School of Civil, Mining and Environmental Engineering


The main objectives for the design of reinforced concrete (RC) columns are to satisfy strength and ductility requirements. High strength concrete (HSC) has been widely used in buildings, bridges and other structures due to its advantages over normal strength concrete (NSC). The use of HSC in lower storey RC columns of high rise buildings leads to the reduction of column sizes. However, the main problem associated with the use of HSC in the construction of RC columns is the lower ductility of the HSC column compared to the ductility of the NSC column for the same amount of confinement reinforcement. This is mainly because the ductility of the concrete decreases with the increase in the compressive strength. A new method of reinforcing concrete columns with steel equal angle (SEA) sections has been investigated in this study. For the same cross-sectional area, a SEA section has a higher second moment of area than a conventional steel bar, which leads to a higher bending stiffness of the SEA reinforced concrete member. In addition, the area of confined concrete is higher in SEA reinforced concrete members than in steel bar reinforced concrete members, which results in higher strength and ductility. It is noted that SEA sections have been extensively used in the construction of the steel structure. However, the influences of the SEA section as longitudinal reinforcement on the behaviour of square HSC columns have not been investigated yet. This study investigates experimentally and analytically the behaviour of square HSC columns reinforced longitudinally with SEA sections under different loading conditions.

The main experimental program of this study included the testing of 32 square high strength concrete (HSC) specimens subjected to different loading conditions. Also, 15 pullout test specimens were constructed to investigate the bond behaviour between reinforcing steel (steel bars and SEA sections) and surrounding concrete.



Unless otherwise indicated, the views expressed in this thesis are those of the author and do not necessarily represent the views of the University of Wollongong.