Model for inelastic biaxial bending interaction of reinforced concrete beam-columns

The paper presents an efficient model for inelastic biaxial bending interaction of reinforced concrete sections. Based on a rate-dependent viscoplastic equation, it is shown that the model is extremely versatile and has the capability to incorporate stiffness and strength decay. The model also enables identification of the physical nature of interaction and achieves a controlled hysteretic behavior. Only uniaxial information is required for the material parameters that describe the model. Unlike other conventional reinforced concrete models, no loop tracing is necessary, thereby making it simple, efficient, and readily suitable for use with large computational models for analyzing reinforced concrete building structures. The validity of the proposed scheme is demonstrated through the analytical simulation of available biaxial experiments on reinforced concrete columns and comparison with other analytical models.