An analytical procedure was recently developed for the nonlinear analysis of reinforced concrete frame structures consisting of beams, columns, and shear walls under monotonic loading. The procedure is distinct from others because it is capable of inherently and accurately considering shear effects and significant second-order mechanisms with a simple modeling process suitable for use in practice. In this study, the procedure is further developed to enable the performance assessment of shear-critical frame structures under general (arbitrary) loading, including the special cases of cyclic and reversed-cyclic loads. Newly developed and implemented formulations are described and applied to 11 previously tested specimens for verification. Important considerations in nonlinear modeling and the limitations of the procedure are also discussed. The procedure is found to accurately simulate the overall experimental behaviors of the specimens examined. Performance measures, such as load and deformation capacities, stiffnesses, energy dissipations, ductilities, failure modes, crack widths, and reinforcement strains, are typically captured well. The procedure exhibits excellent convergence and numerical stability, requiring little computational time.

Beam-column connections are often assumed rigid in traditional frame analysis, yet they undergo significant shear deformations and greatly contribute to story drifts during earthquake loading. Although local joint models are available in the literature for the investigation of single, isolated joints, there is a lack of holistic frame analysis procedures simulating the joint behavior in addition to important global failure modes such as beam shear, column shear, column axial, and soft story failures. The objective of this study is to capture the impact of local joint deformations on the global frame response in a holistic analysis by implementing a joint model into a previously-developed global frame analysis procedure. The implemented joint element simulates joint shear deformations and bar-slip effects. Concrete confinement effects are also considered so that both older and new joints can be modeled. The developed procedure provides better overall load-deflection response predictions including the local joint response.

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A refined constitutive model (called "RDM model") is proposed for simulating the complete stress-strain response of longitudinal reinforcing bars, including the onset of inelastic buckling and subsequent degradation in the post-buckling regime. This model accounts for interactions between lateral ties and longitudinal bars, and is verified using 45 experimental and 58 analytical specimens previously tested by nine research groups. The RDM model is incorporated into a global modeling procedure and validated with six axially loaded columns, 16 axially and laterally loaded columns, and four beams previously tested by nine research groups. The validated procedure is used to study the influences of global second-order mechanisms such as geometrical nonlinearities, shear effects, and confinement effectiveness on the local buckling behavior. The proposed RDM model is shown to provide accurate response simulations for the buckling of reinforcing bars with a wide range of mechanical and geometrical properties. This model employs simple equations and defines full-range compressive response from well-known tensile material properties.