Abstract
This paper reports on the evaluation method of the axial buckling strains of longitudinal steel bars in reinforced concrete columns, subjected to axial load. Two series of experiments were conducted. In series 1, buckling behaviors of bars subjected to compressive axial load only and those subjected to cyclic load reversals, were compared. In series 2, twenty six 15cm square column specimens, confined by various reinforcement, were subjected to compressive axial load only, in order to evaluate buckling strains. The analytical model was developed, taking into account the effects of the diameter of hoops and longitudinal bars and spacing of hoops.
