Non Linear Static Analysis of Bridges with a Modal Pushover Based Procedure

In the last two decades many scientific works on the seismic evaluation procedures for buildings, using nonlinear static analysis (pushover), have been published. Differently there is no much effort available in literature for seismic evaluation of existing bridges, although bridges are strategic infrastructures for every country, with pushover. The aim of the present work is to asses a procedure for existing bridges, using a nonlinear static analysis; the study extends a method proposed for buildings by the same authors (Bergami et al. 2017), the incremental modal pushover analysis (IMPA), that contemplates the two following important aspects that are relevant in the field of seismic analysis of bridges: the intensity of the demand and structural response are correlated; bridges are frequently higher modes sensitive. For all these reasons IMPA for bridges appears as a promising procedure. In this paper the procedure, together with some results of the application on two case study, are presented and discussed.