Flexural Plastic Hinge Length for Reinforced Concrete Frames

The flexural plastic hinge (PH) length is a critical parameter for reinforced concrete (RC) frames subjected to lateral load. In this work, a review of past studies for introducing empirical equations for estimating the flexural PH length ( l p ) of RC frames was introduced. Another key aspect explored in this paper is to study the effect of different available l p equations on the overall nonlinear structural response of RC frames. Therefore, ten l p equations were selected from this review for simulating the nonlinear behavior of two RC frames with available experimental data. Each frame was analyzed ten times with alternative l p values under pushover analysis using SAP2000 software. T he two modeled frames displayed an average error ranging from 12.3% to 23% in the ultimate lateral load, and a deviation ranging from -30.4% to 20.1% in the initial lateral stiffness. These errors indicated that the accuracy of predicting the behavior of RC frames is highly dependent on the chosen l p equation. Finally, the proper l p equation which could represent the nonlinear behavior of RC frames accurately was recommended.