Drift capacity modelling of lightly reinforced concrete columns

Experimental laboratory testing of cast in-situ lightly reinforced concrete columns was conducted to investigate the collapse behaviour and drift capacity of such columns when subject to cyclic lateral loading. Four column specimens with a range of axial load and longitudinal reinforcement ratios were tested. The experimental results indicated that lightly reinforced concrete columns were able to sustain lateral drifts much greater than code and design guideline recommendations whilst maintaining axial load carrying capacity without catastrophic collapse. Complementary theoretical analyses have been developed to model the lateral forcedisplacement relationship for the column by considering each of the flexural, yield penetration, and shear deformation displacement components. The theoretical model was shown to predict the experimental results with very good accuracy and could be used with confidence for further parametric studies involving other column configurations and axial loading scenarios.