Lumped Plasticity Model’s Accuracy in Estimating the Cyclic Response of Low and High-Ductile Reinforced Concrete Frames

The lumped plasticity model has been widely used for the nonlinear analysis of structures due to its simplicity, established guideline in seismic design codes, and less computational effort. However, it has been shown that the accuracy of the lumped plasticity model depends significantly on the plastic hinges’ properties. In this study, the nonlinear behaviors of two similar RC frames but with two different reinforcing detailing were simulated using the lumped plasticity model and the results were compared with those obtained from the conducted experiments on the frames. The effects of using two different plastic hinge models (i.e., ASCE/SEI 41–17 and moment-curvature) and effective stiffness values (i.e. ASCE/SEI 41–17 and Eurocode 8) were investigated. It was observed that the employed plastic hinge models had insignificant effect on the frames’ ultimate loads and both were able to estimate the ultimate loads accurately. However, the models underestimated the displacements corresponding to the ultimate loads of the frames. The failure modes of the frames were also estimated accurately.