Application and Assessment of Equivalent Linear Analysis Method for Conceptual Seismic Retrofit Design of Háros M0 Highway Bridge

In this study, seismic performance of the existing M0 Háros Highway Bridge in Hungary is evaluated. The large-span bridge is designed with minimal consideration of seismic actions, seismic resistance of certain piers, bearings and pile foundations is not adequate. Eight different demand mitigation methods are evaluated considering quasi-elastic configurations as well as non-linear systems adopted with non-linear anti-seismic devices (NLASD). To accelerate the preliminary design phase, an equivalent linear analysis (ELA) methodology is worked out. Keeping in mind the limitations of the ELA method, non-linear timehistory analysis (NLTHA) is also applied for the retrofitted configuration for validation purposes. Comparison of the two methods shows that the ELA method gives the designer adequate, still conservative results for optimal retrofit decisions.