Back analysis for earthquake damaged bridges. Part II: Application to a viaduct damaged in the April 6th, 2009 L'Aquila earthquake.

In order to verify the applicability of the methodology illustrated in the companion paper (Sebastiani et al., 2012) to practical engineering problems, a case study is presented. The examined structure is an existing curved highway viaduct, named "Popoli viaduct", located in the Abruzzo region (central Italy). The bridge consists of two distinct concrete decks that are continuous over the piers, each with 12 spans for a total length of about 460 m. The bridge was built during the decade from 1970 to 1980 and it wasn't equipped with seismic protection devices, so the decks are simply supported by steel cylindrical bearings. The viaduct is situated in an alluvial basin and it was damaged by the L'Aquila earthquake on April 6th, 2009. Starting from the observed damage suffered by the bridge, this paper presents an example of the Back Analysis method presented in the companion paper. The observed damage state has been reproduced by an acceptable degree of precision considering the high amount of uncertainty involved in the analysis, tentatively indicating the method could be a suitable tool for engineers facing this kind of problems. © 2012 Taylor & Francis Group.