Study on FE models in elasto-plastic seismic performance evaluation of steel arch bridge

• We proposed a numerical method for seismic performance evaluation of complex steel bridges.
• We proposed a practical formula through parametric study to predict the seismic damage length on a steel member.
• The advantages and deficiencies of FE models to assess seismic performance of steel bridges were carefully investigated.
• Seismic performance of a steel bridge was examined using both nonlinear static and dynamic time-history analysis procedure.

This paper studied the impact of various structural parameters on the length of damage zones of steel box girder under cyclic load using elasto-plastic FE model and proposed an empirical equation to estimate the length of the seismic damage zone. To verify this empirical equation, a multi-scale model as well as a fiber model of a half-through steel arch bridge of 130 m span was created. Pushover analysis and nonlinear seismic time–history analysis were performed using these two models. The results from the numerical analysis of this arch bridge indicate that the majority of seismic damages of this bridge occur near the joints and connections. The multi-scale model shows a good performance in predicting both of the displacement response and the propagation of seismic damage zones. Main structural components of the structure are less likely to experience low-cycle fatigue failure. Fiber model can accurately estimate the global displacement response and the general distribution of plastic regions across the entire bridge, but it cannot give detail information about the size of plastic zones.