Best-fit models for nonlinear seismic response of reinforced concrete frames

This paper identifies the optimal combination of hysteresis-modeling and damping parameters for use in practical nonlinear dynamic analysis to obtain satisfactory correlations in both amplitude and waveform between the calculated and measured seismic response of reinforced concrete frames. In this study, frame members are characterized by five modeling parameters: initial stiffness, bond–slip rotations, post-yield stiffness, unloading stiffness, and viscous damping. The calculated response is compared with measured data from three small-scale shake-table multistory test structures and from a seven-story instrumented building. The three test specimens (structures MF1, MF2, and FNW) are each analyzed for two different base acceleration tests whereas the seven-story building (Holiday Inn at Van Nuys, CA) is analyzed using a single recorded seismic event (1994 Northridge) in each of the two principal directions of the building (structures HNS and HEW). Analyses for all five structures are carried out using three different computer programs. The goodness-of-fit of the computed response to the recorded experimental data is measured by the Frequency Domain Error (FDE) index. Simplified rules are presented to derive the best modeling characterizations that give consistent low values of FDE for the various structures and structural analysis programs considered.