Ultimate Limit State Response of Reinforced Concrete Columns for Use in Performance-Based Analysis and Design

The design of reinforced concrete structures for extreme events requires accurate predictions of the ultimate rotational capacity of critical sections, which is dictated by the failure mechanisms of shear, hoop fracture, low-cycle fatigue and longitudinal bar buckling. The purpose of this research is to develop a model for the full compressive behavior of longitudinal steel including the effects of bar buckling. A computational algorithm is developed whereby experimental data can be rigorously modeled. An analytical model is developed from rational mechanics for modeling the complete compressive stress-strain behavior of steel including local buckling effects. The global buckling phenomenon is then investigated in which trends are established using a rigorous computational analysis, and a limit analysis is used to derive simplified design and analysis equations. The derived buckling models are incorporated into wellestablished sectional analysis routines to predict full member behavior, and the application of these routines is demonstrated via an incremental dynamic analysis of a ten-storey reinforced concrete building. The buckling models and the sectional analysis routine compare favorably with experimental data. Design recommendations and topics for further research are presented.