Drift performance of lightly reinforced concrete columns

This paper presents the findings of a research project investigating the lateral load drift behaviour of lightly reinforced concrete columns. Such columns are common in regions of low–moderate seismicity, and although their strength properties are well defined, the drift performance is less understood. The paper presents the results of an experimental study undertaken and the development of a theoretical model for predicting the lateral load–drift behaviour of lightly reinforced concrete columns. The model includes a study undertaken to estimate the drift capacity of lightly reinforced columns at lateral load failure and axial load failure based on a large database of previous experimental tests. The results of a case study example are presented and clearly indicate the dramatic impact that the axial load ratio has on the drift performance of lightly reinforced columns, particularly the significantly lower drift capacities that are available in compression dominated columns.