Seismic assessment of typical existing Italian bridge

The paper illustrates the seismic performance assessment of a bridge substructure simulating typical existing Italian highway bridges . The reference structural system is a reinforced concrete (R C) 1:3 scale single span bridge, tested on the shaking table system at the University of Naples, Italy. The testing facility consists of two 3m x 3m square shake tables . Low strength concrete and smooth bars were used for the bridge sub - assemblage to study the response of existing RC bridges without adequate seismic details . Different support conditions, namely simply supported and base isolated, were considered in the testing program. Natural historical records were used as earthquake strong motions, scale d at increasing peak ground accelerations. The results of the experimental incremental dynamic analysis on the “as built” structure, are used to evaluate the effectiveness of base isolation strategies commonly adopted for the seismic retrofit of the bridge deck.