The Assessment of Seismic Residual Displacement of Concrete One Column Bent Bridges with Forced-Based Fiber Elements

The force-based formulation is attractive because it can model the spread of plasticity along the length of column using only one element and a number of integration points; however¡ their sensitivity to modeling parameters and models of material behavior has resulted in the estimation of residual displacement seismic demand to be important in this modeling method. In this research¡ the effects of two theories of lumped plasticity and distributed plasticity on modeling the concrete bridge column for estimating the residual displacement in near field zones were investigated. For estimation of residual displacement¡ the effects of reinforcing slide¡ geometrical parameters¡ and material behavior parameters were studied. Due to the importance of residual displacement in the performance evaluation of damaged structures¡ estimation of residual displacement is very crucial. In this study¡ the effects of different modeling methods as well as material behavior parameters on estimation of residual displacement were investigated. For this purpose¡ five different models were studied and the sensitivity of optimum model to various parameters was evaluated. The results showed that the theory of distributed plasticity for bridge concrete column has a good accuracy for estimating the residual displacement. Reloading strain parameters of concrete behavior and forced-based beam-column fiber element modeling parameters have an important role in estimation of residual displacement.